No matter what the activity, mistakes are always the most costly thing.

Even digging a hole, if you dig in the wrong place you've more than doubled the work. Accidentally putting a copyrighted work into your art could cost millions. Buffer overflow will cost way more than the code it's in.

Unsupervised, AIs make way more mistakes than even the dumbest person so the more you just stick AI in something the more it'll cost.