5 common ROI mistakes B2B marketers are still making

Measuring marketing ROI is crucial – yet many marketers continue to make similar mistakes when trying to prove the value of their efforts. In the rush to justify budgets, errors in calculating and interpreting ROI are common.

Here, we identify five frequent mistakes that B2B marketers, including those in the UK, are still making when measuring ROI and offer solutions to correct them. By addressing these mistakes, marketers can avoid misleading results and ensure they focus on strategies that genuinely drive returns.

1. Chasing vanity metrics instead of business outcomes

One of the biggest ROI pitfalls is focusing on the wrong metrics—those that appear impressive on the surface but do not reflect real business value. These vanity metrics include website visits, social media likes, email open rates, and raw lead volumes.

For example, a 200% increase in web traffic or thousands of leads from a content syndication campaign may look like a success. However, if those visitors never convert or the so-called leads are simply random contacts who do not progress in the sales funnel, these numbers mean little in terms of ROI.

The mistake

Equating activity with impact. For instance, calculating ROI as “We got 1,000 webinar sign-ups for a £5k spend, so that’s £5 per lead—great ROI!” without verifying whether any of those sign-ups turned into actual opportunities or revenue. High numbers can create a false sense of success.

How to fix it

Align ROI calculations with meaningful business outcomes—such as revenue, pipeline generated, and customer acquisition. Instead of measuring cost per click or cost per lead, focus on cost per SQL or cost per acquired customer.

For example, instead of reporting that a whitepaper received 5,000 downloads, track how many of those downloads converted into sales-qualified leads or customers. Calculate ROI based on the revenue from those deals relative to the initial spend.

In practice, if a £50k campaign generates 500 leads, do not stop at “£100 per lead” as the key metric. Instead, determine how many of those 500 leads converted into, for instance, 10 customers worth £200k total. Now, evaluate ROI as £200k return on £50k spend (a 4x return). That is a real ROI story.

Additionally, educate teams and leadership on the difference between vanity metrics and value metrics. Vanity metrics may still be useful as early indicators, but they should always be connected to down-funnel performance.

For example: “Our eBook received 1,000 downloads (vanity metric), which yielded 50 MQLs and ultimately 5 deals worth £X (value metric).”

The ROI discussion should always focus on the financial outcome (£X) and how it compares to the marketing spend.

2. Ignoring long-term and long-cycle effects (short-term focus)

Many marketers make the mistake of measuring ROI over too short a timeframe, particularly in B2B, where sales cycles are long and deals may materialise months after the initial marketing touchpoint. Campaigns are often expected to generate immediate revenue, and if results are not visible within the same quarter, they are deemed failures.

This short-term approach can severely undervalue marketing’s true ROI. In the UK, 87% of B2B marketers say they struggle to measure the long-term effects of their initiatives due to extended buying cycles. As a result, they default to a monthly or quarterly reporting cycle that does not accurately reflect the long-term nature of B2B buying. This can lead to pulling the plug too soon on effective initiatives or failing to credit marketing efforts that deliver returns later.

The mistake

Measuring ROI in isolation for each quarter or campaign and failing to account for delayed impact is a common pitfall.

For example, a marketer might run a thought leadership event costing £30k and, after one month, see no direct sales. They might conclude that the campaign had a poor ROI simply because immediate revenue cannot be attributed to it. However, six months later, the event may have influenced multiple opportunities that eventually closed, delivering a strong ROI. If only short-term data is tracked, this long-term impact is missed.

A similar mistake occurs with content marketing and brand-building activities. The ROI of these efforts accrues over time as brand awareness grows, leading to more organic leads and improved conversion rates. Many marketers cut these activities because this quarter’s ROI looks low, even though the long-term returns may be substantial.

How to fix it

Extend the ROI measurement horizon. Use longer attribution windows and track cohorts of leads and customers over time. If the average sales cycle is nine months, evaluating a campaign’s ROI after just two months is premature.

Implement a system, such as a CRM with campaign attribution or marketing automation tracking, that allows outcomes from each campaign to be monitored over the long term. Metrics such as 12-month pipeline or 12-month revenue attributable to marketing efforts provide a more accurate reflection of marketing’s impact.

Another key adjustment is to embrace long-term value metrics, such as customer lifetime value (CLV). A major mistake in ROI measurement is failing to consider the lifetime revenue from a customer, instead focusing only on the initial sale.

Marketers may assume a campaign’s ROI is based purely on the first contract value. However, in B2B, customers often renew or expand their contracts over time. As one analysis pointed out, “only focusing on acquisition” provides a misleading picture of ROI.

For example, if a company spends £10k to acquire a customer who initially spends £10k, the ROI appears to break even. However, if that customer goes on to spend £50k over five years, the true ROI is much higher. Incorporating CLV into ROI models helps prevent the undervaluation of marketing efforts.

3. Failing to integrate marketing and sales data (siloed measurement)

Another frequent mistake in ROI measurement is analysing marketing performance without a complete dataset, often due to silos between marketing and sales data. For example, marketing teams may track the number of leads and estimate revenue based on assumed conversion rates but fail to reconcile this with actual sales figures later. Similarly, they may report on marketing-generated pipeline in isolation, which can lead to double counting or missing key data if it is not properly integrated with the CRM.

According to The Marketing Centre, “not having a complete data set” is one of the primary reasons why ROI calculations can be misleading. If marketing ROI analysis does not include sales outcomes from the CRM (e.g., Salesforce) and financial costs from finance teams, then the picture is incomplete.

The mistake

Data disconnects lead to incorrect ROI calculations. Common examples include:

• Not tracking marketing-sourced leads through to closed deals in the CRM, leading to over- or under-estimating the revenue marketing actually contributed.
• Using only platform-specific data (such as Google Analytics conversions or LinkedIn leads) without linking them to actual customers in the database. This approach may show ROI per channel in isolation, but without tying leads to closed sales, the results can be misleading.
• Ignoring certain costs in ROI calculations, such as marketing staff time or creative costs, which can inflate ROI figures. Conversely, failing to account for revenue influenced by marketing—because sales “owns” the account in the CRM—understates marketing’s impact.

A practical scenario

Marketing reports a 10x ROI for a campaign by claiming it generated 100 demo requests. Based on historical data, 10% of demo requests convert to sales, with an average deal size of £50k, meaning expected revenue is £500k from a £50k campaign spend.

However, if those demo requests are not correctly logged as opportunities, and sales only converts five of them into actual deals worth £250k, the true ROI is half of what was originally reported.

Conversely, if sales closes deals that marketing nurtured, but marketing is not tracking its influence, ROI may be significantly underreported.

How to fix it

Integrate and validate data across systems. Every lead source and campaign should be tagged and tracked in the CRM so that marketing can attribute revenue to specific initiatives once deals close.

Marketing teams should work closely with sales operations and BI teams to obtain reports on actual revenue generated. ROI calculations should be based on the same revenue figures used in financial reports, ensuring consistency.

Key steps for integration

• Connect marketing automation platforms to the CRM, enabling full MQL-to-SQL-to-closed-loop reporting.
• When computing ROI, use actual closed-won revenue that marketing influenced, within an agreed attribution model.
• Avoid duplicate counting—if multiple campaigns contributed to a deal, do not count each one as if it fully generated the sale. Instead, use weighted attribution models to distribute credit fairly.
• On the cost side, be transparent and consistent—include media spend, content creation, agency fees, and relevant salary costs if conducting a true ROI calculation. Some businesses exclude salaries from campaign ROI and classify them as overhead, but whatever approach is used, it should be clearly defined and applied consistently.

Pro tip

Hold a regular reconciliation meeting between marketing, sales, and finance teams. At the end of each quarter, review all closed deals and ensure that marketing has visibility into which deals were marketing-generated or influenced.

Making ROI reporting a collaborative effort prevents situations where marketing reports figures that sales or finance later question due to discrepancies. A unified dataset ensures credibility and trust in the numbers.

By integrating data properly, marketing teams can also gain deeper insights into the profitability of different lead sources.

For example, marketing may generate a large number of leads from a particular channel, but sales data might reveal that these leads result in low-value deals or one-time buyers with a low customer lifetime value (CLV). With this insight, marketing can adjust strategy to focus on sources that produce high-value, long-term customers, improving true ROI in the long run.

4. Using one-size-fits-all attribution (last-click bias)

Attributing revenue entirely to a single touchpoint—often the last click or last touch—remains a common mistake that distorts ROI calculations. This often happens due to reliance on default analytics settings or an effort to simplify attribution for reporting.

For example, if a customer had five marketing touchpoints but the final interaction (such as a direct visit or a sales call) receives 100% of the credit, marketing may appear to have no ROI from earlier touchpoints—which is inaccurate. Despite this, 41% of businesses still use last-touch attribution for online channels, meaning they are likely miscrediting marketing efforts.

The mistake

Misattribution of conversions leads to wrong conclusions about ROI. Common symptoms of this mistake include:

• Upper-funnel channels (such as content syndication, social media, and display ads) appear to generate no direct ROI in reports, leading to budget cuts, even though they assist conversions.
• Over-investment in closing channels (such as branded search or retargeting ads) because they appear to have huge ROI, when in reality they are simply benefiting from groundwork laid by other efforts.
• Marketers declaring “X campaign generated zero ROI” simply because it was not the final touchpoint—ignoring its influence in warming the lead.

For instance, consider a prospect who:

1. First discovers your company via an SEO-driven blog post
2. Later attends a webinar
3. Finally clicks a retargeting ad and signs up for a trial

A last-click model would attribute all revenue to the retargeting ad campaign, ignoring the earlier content and webinar that nurtured the lead. If ROI is judged solely by last-click, marketers may wrongly deprioritise content and webinars, weakening their marketing mix over time.

How to fix it

Adopt a multi-touch attribution approach for ROI analysis. This does not need to be highly sophisticated—even a simple weighted model is better than last-click attribution.

Possible models include:

• First-and-last touch weighting – Assign 50% of credit to the first interaction and 50% to the last.
• Linear attribution – Distribute credit evenly across all touchpoints.

The goal is to acknowledge that multiple marketing interactions contribute to a sale. If possible, leverage AI-driven or data-driven attribution models (many CRMs and analytics platforms now offer this) to distribute credit more accurately.

When calculating ROI, attribute a portion of revenue to each campaign or tactic involved, then compare revenue to costs. This approach ensures that supporting tactics show ROI, giving a more accurate picture of what is driving growth.

5. Overlooking the quality of spend (not all ROI is equal)

A common but often overlooked mistake in ROI measurement is treating all returns as equal and failing to analyse the quality of those returns or the efficiency of spend per channel. Marketers might report, “Overall, our marketing ROI is 300% this year,” without examining variations and underlying issues. This can mask problems such as diminishing returns or inefficient spend, which could be dragging down overall performance.

The mistake

Not all ROI is of equal quality, and failing to analyse where and how efficiently revenue is generated can lead to misleading conclusions. Key issues include:

• Marginal ROI neglect – Failing to assess which part of marketing spend produces the highest incremental ROI. For example, the first £100k in Google Ads might generate strong ROI, but the next £50k may only break even. If ROI is only assessed at a blended level, marketers might continue increasing spend without realising that additional investment is no longer delivering meaningful returns.
• Ignoring the cost of complexity – Some marketers invest in too many small programmes, each of which generates modest returns. The overall ROI may be positive, but managing 10 average-performing programmes may be less efficient than focusing on five high-performing initiatives. The mistake is spreading resources too thinly, when consolidating spend into fewer, higher-performing efforts could yield stronger results.
• Failure to measure incremental lift – Some reported ROI figures are based on conversions that would have happened anyway. For instance, running retargeting ads to prospects already in the pipeline may make it appear as though those ads converted the customer. However, if those leads were likely to convert regardless, then the true incremental ROI may be negligible. If this is not accounted for, ROI figures can become overstated.

A common mistake is continuing to equally invest in all campaigns simply because their ROI is positive. A smarter approach would be to analyse why high-performing campaigns are successful and scale those efforts instead.

How to fix it

Optimise for higher-quality ROI by taking a deeper approach to analysis.

• Assess ROI by channel, campaign, and audience segment – Identify where ROI is highest and lowest. Then, determine whether low ROI areas can be improved or whether resources should be shifted. Avoid making decisions based on blended averages.
• Use incrementality testing – In digital marketing, this could involve holdout groups. For example, run retargeting ads to 90% of a target audience but hold back ads for 10%, then compare conversion rates. If the exposed group does not significantly outperform the holdout group, the retargeting spend isn’t truly generating additional revenue.
• Consider saturation effects – If one more pound in Channel A generates significantly less return than in Channel B, budget should be redistributed. This is a basic principle of marketing optimisation, yet many teams fail to adjust budgets based on diminishing returns.
• Evaluate ROI in relation to CAC and LTV – A common mistake is assuming that 2x ROI is universally good. However, if the business model expects a 5x return (due to factors such as high churn or operational overheads), then 2x might actually be unprofitable. Ensure ROI targets align with broader business economics. For example, if CAC is creeping towards LTV, then even a technically positive ROI may indicate that marketing spend efficiency is declining.

ROI as a decision-making tool

By refining how ROI is evaluated, it transforms from a superficial metric into a powerful decision-making tool.

The goal is not simply to report a positive percentage but to maximise the business impact of marketing spend.

Avoiding these five common mistakes will help marketers gain credibility with leadership, optimise budget allocation, and ultimately drive more revenue with the resources available.