The definition
What is FOMU?
FOMU — the Fear of Messing Up — is a term coined by Brittany Martin Déjean for the pattern of overthinking, second-guessing and self-criticism that shows up before, during and after a mistake.
Not a personality trait
FOMU isn't who you are. It isn't the price of being successful. It's a habit loop that's been running in the background — and once you can see it, you can interrupt it.
The FOMU cycle
1 · Before the mistake
The Fear
Overthinking, rewriting, holding back the idea.
2 · When it happens
The Mistake
The meaning we attach to falling short.
3 · After
The Recovery
Self-punishment that restarts the loop.
The cost
If you're losing even 5 hours a week to FOMU, that's 6.5 work weeks a year.
How FOMU shows up at work
- Ideas left unshared.
- Emails rewritten for hours.
- Feedback softened or skipped.
- Meetings replayed at 2am.
- Decisions delayed.
- Wins brushed off.
FOMU, frequently asked
Is FOMU the same as FOMO?
No. FOMO is the fear of missing out. FOMU is the fear of messing up.
Is FOMU the same as perfectionism?
No, but a lot of FOMU behaviors are perfectionistic tendencies. You can have FOMU without identifying yourself as a perfectionist.
How does FOMU relate to psychological safety?
Psychological safety is about having environments where people feel safe to be their true selves, share ideas and be wrong without shame. FOMU identifies the pattern that individuals carry that form cultures and habits that undermine a team's performance.
Who coined FOMU?
Brittany coined FOMU while working in disability inclusion to name the behavior of nondisabled people who were awkward and uncomfortable about disability. In 2026, she expanded the scope of FOMU to include the pattern of behaviors people fall into before, during and after a mistake.
For yourself
Curious where FOMU shows up for you?
Take the 2-minute FOMU Score quiz → (opens in a new tab)