For simplicity's sake lets focus on bugs created when users fail to consider edge cases. We could say 100% of these bugs are caused by people failing to consid

For simplicity's sake lets focus on bugs created when users fail to consider edge cases. We could say 100% of these bugs are caused by people failing to consider edge cases, and if developers accurately considered all edge cases then we would have 0 bugs. To then think that this problem is solved because we can tell a developer "consider all edge cases" even though it has 0 effect on the actual bug count caused by edge cases is absurd.