What kills me personally is that I'm constantly 80% there, but the remaining 20% can be just insurmountable. It's really like gambling: Just one more round and it'll be useful, OK, not quite, just one more, for hours.
I find the latter a lot more challenging to cut my losses when it's on a good run (and often even when I know I could just write this by hand), especially because there's as much if not more intrigue about whether the tool can accomplish it or not. These are the moments where my mind has drifted to think about it the exact way you describe it here.
Sometimes it looks like some of that comes from AI generally being very very sure of its initial idea "The issue is actually very simple, it's because..." and then it starts running around in circles once it tries and fails, you can pull it out with a bit more prompting, but it's tough. The thing is, it is sometimes actually right, from the very beginning, but if it isn't...
This is just my own perspective after working with these agents for some time, I've definitely heard of people having different experiences.