HiPPO Effect
Without evidence on the table, the most senior person's preference becomes the decision. (HiPPO = Highest Paid Person's Opinion.)
Why PMs should care
Without evidence on the table, the most senior person's preference becomes the decision.
This isn't always a bad thing. Senior people usually have more context, more scars, and more information about the wider business than the team in the room. It becomes a problem when seniority overrides well-researched PM work without actually engaging with the research.
The failure mode is rarely 'the exec is wrong'. It's 'the exec didn't see the data in time to change their mind'.
The defence is almost entirely about preparation. Know which decisions a senior person is likely to have an opinion on. Bring the data before the meeting, in a format they can read in two minutes. And where it matters, pre-share the conclusion in a 1:1 so the meeting confirms a decision that's already been made — instead of creating one in real time under social pressure.
Example in product work
A VP walks into the weekly product review and says, confidently, 'the new CTA button should be green — it'll feel more positive'.
There is actual A/B test data showing that, for this specific page and audience, blue converts 12% better than green.
The PM either:
(a) has the result in a one-pager they can pass across the table in thirty seconds, or
(b) does not, and the meeting goes green.
Case (b) is not a failure of the A/B test. It's a failure of pre-meeting preparation. The test's existence doesn't matter if nobody's been shown it.
The senior PM move: pre-read the VP on the result in a Monday 1:1, so by the time the meeting happens, the VP is the one saying 'we tested this, blue wins'.
What to do when you see it
- It's not always bad — senior people usually have more context, more scars, and more business information than the team in the room.
- It becomes a problem when it overrides well-researched work without engaging with the research.
- The failure mode is rarely 'the exec is wrong'. It's 'the exec didn't see the data in time to change their mind'.
- The defence is preparation: know which decisions a senior person will have an opinion on, and pre-share the data in a format they can read in two minutes — before the meeting.
Sources & further reading
- Seven Pitfalls to Avoid When Running Controlled Experiments on the Web — Crook, Frasca, Kohavi & Longbotham, 2009The Microsoft research paper (Kohavi et al.) that popularised the term HiPPO in the context of experimentation — hosted on Kohavi's own experimentation platform.
- Trustworthy Online Controlled Experiments — Kohavi, Tang & XuThe canonical book on data-driven decision making by the Microsoft / Airbnb experimentation experts who named the HiPPO.