[cj]

I run a 20+ person tech company.

People screw up and make mistakes all the time.

I'd have no employees if I fired everyone after every mistake. I'm almost certain the same is true of virtually every company on earth.

What really matters is how people handle themselves and others when failures occur, which is what the OP is asking about. Very valid question. Unfortunately a lot of low quality responses in the comments so far.

From my POV, mistakes/failures are a fact of life, you can't avoid them. So instead, you have to manage the risk of failures/mistakes and work to reduce that risk until it's at a risk level where management is comfortable. At in IC level, that probably means doing retrospects on major failures, why they occured, how to avoid in the future... and most importantly, focus the retros on the -process- rather than the -people-. Processes can be easily and quickly improved.. "this slipped through QA because it's not on our QA checklist" compared to "Bob is a bad coder, it's his fault"