We criticize engineers who drop into a code base and try to make changes without understanding. You can be forgiven for doing it a few times, but after that you're doing it intentionally. And if they hired engineers that didn't know this, that's incompetence at both levels.
Not only is this different code bases and IT products, it's across organizations and done very rapidly.
I am also not convinced that they don't simply have malicious intent most of the time.