Probably because the things they do aren't up to scrutiny. You don't know it's bad until someone/something comes along and tells you, or you just happen to disc

Probably because the things they do aren't up to scrutiny. You don't know it's bad until someone/something comes along and tells you, or you just happen to discover a better way on your own (that someone else has probably already discovered). The computer doesn't shock you if you write terrible code, after all.