Because they always think they’re the exception and everyone else is doing it wrong.

They are wrong in this belief because being idiots they don't have the capacity to be aware that they are idiots. But generally this belief is true. It is more positively expressed in these words: “If you want something done right, you have to do it yourself.” When I look at the dismal state of software, I see crap everywhere. With the rise of slop generators this is bound to become worse.