This is my main gripe with some newcomers of projects I have worked on. They tend to spit out destructive criticism towards legacy code with such an ease and w

This is my main gripe with some newcomers of projects I have worked on. They tend to spit out destructive criticism towards legacy code with such an ease and without any context on why things are the way they are. My usual response, albeit in a more polite manner, is something along the lines of: "Yes I know the code in this part of the system is not as nice as other parts. And if you bothered to ask why, I'd tell you it's because this code is 6 years old and we learned better ways to do the same thing since. It's called technical debt and we are always working to reduce it. There's no need to demoralize the engineers that worked on that part of the system."