First big mistake at a new job? Own it before anyone finds it. Speed turns a disaster into a footnote.

The cost of an error at work is mostly the cost of the delay before anyone can fix it. Told early, it is a problem with a solution and you are the person who flagged it. Discovered later, it becomes two problems, the original one and the question of why you said nothing, and the second is always worse.

If something has gone wrong, say so today, to whoever can act on it. Lead with the fact, then with what you think the fix is. Nobody remembers the mistake for long. They remember whether they had to find it themselves.