Third-Party ROI Studies vs. Vendor Case Studies: What to Actually Trust

When GitLab reported its Q2 fiscal 2027 results, it cited a specific figure: an independent Forrester Consulting Total Economic Impact study found organizations achieve a 400% return on investment with its Duo Agent Platform. That's a materially different kind of claim than a vendor's own case study, and most buyers evaluating enterprise software don't consistently distinguish between the two when a sales deck says 'proven ROI.'

The Real Difference Between the Two

• A vendor case study is typically written or commissioned by the vendor itself, often highlighting a single best-fit customer, with a methodology that's rarely disclosed in full
• A third-party ROI study, like Forrester's Total Economic Impact framework, is conducted by an independent research firm using a defined, published methodology, typically interviewing multiple customers and modeling costs and benefits with disclosed assumptions
• The independent study doesn't guarantee accuracy for your specific situation, but it removes the vendor's own incentive to cherry-pick the best possible outcome as the headline number

Questions to Ask When a Vendor Cites an ROI Number

• Who actually conducted the study — the vendor internally, or an independent research firm with a disclosed, named methodology?
• How many customers were interviewed or modeled, and were they selected by the vendor or independently sampled?
• What specific costs and benefits went into the calculation, and are the underlying assumptions published or just the final headline percentage?
• Does the study's customer profile actually resemble your organization's size, industry, and use case, or is the 400% (or whatever the number is) coming from a best-case scenario that doesn't generalize to you?

The Practical Standard to Apply

Treat a vendor's own case study as a data point worth reading, but not as evidence on its own — it's marketing material with a real customer's name attached. Treat an independently conducted, methodologically transparent study (Forrester's TEI framework being one well-established example) as meaningfully stronger evidence, while still checking whether the study's participant profile actually resembles your situation before assuming the headline number applies to you. The distinction is worth making explicit the next time 'proven ROI' comes up in a sales conversation — ask which kind of proof you're actually being shown.