Bugs get missed in testing because developers can't anticipate all the ways users can break it. That is why beta testing exists. There are also bugs that are r

Bugs get missed in testing because developers can't anticipate all the ways users can break it. That is why beta testing exists. There are also bugs that are rare and take lots of effort to fix. You can first see how often that bug actually occurs in the wild before prioritizing it. Sometimes it never occurs or if it does happen, the user can recover from it easily so it doesn't break your product.