Why Attribution Alone Cannot Prove Event ROI

As pressure mounts on B2B marketing budgets, events are under increasing scrutiny. Marketing leaders are being asked to justify spend, prove revenue impact, and defend event investments with the same rigor applied to sales and operations. According to Forrester’s Q1 2025 State of B2B Events Survey, more than 90 percent of organizations cite demonstrating ROI as a top priority for their events teams. Yet many are relying on attribution models that were never designed to tell the whole story.

Attribution feels like a logical solution. It assigns credit to marketing touchpoints that precede a conversion and promises a clear line from activity to revenue. For events, this often means attributing pipeline or closed revenue to event attendance within a specified time frame. While useful, attribution alone cannot answer the question executives actually care about: what did this event contribute to revenue outcomes?

The core issue is that attribution measures touchpoints, not impact. B2B buying journeys are long, complex, and nonlinear. Events rarely operate as a single decisive moment. Instead, they influence deals by accelerating buying cycles, increasing deal size, strengthening account relationships, or reinforcing confidence across buying committees. These effects are incremental and cumulative, and they do not show up cleanly in timeline-based attribution models.

Attribution also struggles to distinguish correlation from causation. A deal that closes after an event does not necessarily close because of the event. When multiple channels are active simultaneously, attribution distributes credit without explaining which investments actually contributed to the outcome. The result is a report that shows activity, but not actual business value.

Forrester’s research highlights how structural challenges compound the problem. Budgets are flat or declining for roughly two-thirds of event teams, while attendee satisfaction scores are dropping and buyer expectations are rising. At the same time, more than a quarter of large organizations now use six or more event technology platforms. Yet, only about one in five have fully integrated their primary event platform with sales and marketing systems. This fragmentation limits visibility and undermines confidence in attribution-based ROI claims.

At DemandLab, we believe this is why attribution should not be the end goal. Instead, marketers need to shift toward measuring marketing contribution. Contribution focuses on how marketing investments influence revenue performance overall, rather than how credit is divided across touchpoints.

Marketing contribution asks a fundamentally different question: how much revenue would the business have lost if this marketing activity had not occurred? This approach evaluates net impact on pipeline creation, pipeline acceleration, and revenue conversion. It places events within the broader revenue engine instead of isolating them as a single-channel metric.

For example, rather than assigning a percentage of credit to event attendance on a closed deal, contribution analysis examines whether the event meaningfully changed the deal trajectory. Did it increase win rate, shorten sales cycles, expand deal size, or re-engage stalled opportunities? These are outcomes executives recognize as value.

As outlined in DemandLab’s marketing contribution benchmarking framework, contribution measurement improves as organizations mature their data, governance, and alignment between marketing and sales. Contribution should trend upward over time, reflecting marketing’s growing influence on revenue outcomes rather than fluctuating based on attribution rules.

In a climate where events are under pressure to justify every dollar, marketers must move beyond attribution as a proxy for value. Attribution can support analysis, but it cannot stand alone as proof of ROI. Marketing contribution provides a clearer, more credible lens for demonstrating how events drive business results and why they deserve continued investment.

Read this blog to learn more about DemandLab’s approach to benchmarking marketing contribution.