It depends very much on how I got the contractor. For the most part, contractors I was sent to by other businesses have been good. Independent ones I've found through Angie's list or whatever, generally not so much but not universally bad.

I've hired a couple of painters who clearly figured they could get high and hang out with a buddy in my house while slopping paint on walls and ogling daughters. One represented himself as bonded but when I did my research (after) I found he wasn't even registered as a business. He did a shit job and I'd supplied the paint and all supplies.

I told him I wasn't going to pay his asking price because the quality was so bad, but I'd pay half acknowledging that he had in fact spent a fair bit of time getting the job done. He could accept it or I would fight paying anything and report him. He accepted the half, which I think was fucking generous.

That aside, I've had good painters, a good experience installing an above ground pool (other than it was clearly just a side gig and I had to act as my own foreman to tell people what needed to be done), good deck builders, had granite installed by a Lowe's contractor and that went just fine. None of it was show it off in a magazine quality, but all decent enough craftsmanship. But I'm also aware of how long it would take and how bad I'd fuck it up myself or how bad I'd hurt my back, so I'm not super demanding of perfection.