[mattbrewsbytes]

Knowing edge/corner cases is experience based. You have to understand the business domain to really understand how those types of things come up. As a senior dev starting at a new company less than 2 years ago, I still don't recognize edge cases as often as others that have been there longer.

I would suggest checking your work might help. Put it down and do something else, then come back to it and pretend you are doing a code review of it.

When you state final quality of code, your work doesn't need to be perfect before another human looks at it. That is why we work in teams. I'm not saying be sloppy on purpose but if QA is coming up with trivial test additions, just add them. People should have feedback on code reviews.

If the mistakes you are making are trivial, we've all made them and all still make them. Syntax errors and mis-typed variables trip me up all the time. Those are usually easy to find because the code doesn't work. If the mistakes are more design related then get some software design reviews from a senior dev before going deep into having code written.