For many people, self-editing is a skill before it is a problem. If you learned early to read a room, to check how you were coming across, to not take up more space than was safe, that vigilance protected you. It also becomes the default narrator of your career, and that narrator systematically understates you.
You can see it in the sentences. "I helped with" for work you led. "We" for a decision you made alone. "It was mostly luck" for a result you engineered. "I'll wait until I have more evidence" for a conversation that is already overdue. Each edit is small and defensible. Together they mean the people deciding your future are working from a version of you that you wrote down, and shrank.
The fix is not affirmation. It is checkability. Write what happened in language someone else could verify — what the situation was, what you did, what changed. Doubt cannot survive very long against a specific record; it thrives on summaries. And where a doubt does survive the evidence, you have found something genuinely worth developing, which is useful rather than shameful.
One caution that matters here: not every hesitation is irrational. If you are in an environment where being fully yourself has real costs, some of your caution is accurate risk-reading. The aim is not to override your instincts. It is to separate the parts you can act on from the parts that belong to the environment, so you stop paying for both as if they were personal failings.