The worst gun I have ever shot was an LC9. That was the absolute worst trigger I have encountered. The guy who owned it was so proud of it. He couldn't hit anything with it either.
The worst I have owned was a S&W third generation .40. I have owned over a dozen third gen Smiths and they have all been great, except that one. I would have been a lot more accurate throwing the gun at seven yards then firing it. I let a couple friends try it. I always assume it's me. They concurred that it sucked and couldn't hit anything with it either.
As of now, a Glock 42. Got it a couple of weeks ago, haven't found any ammo the it cycles reliably,
FTE's and stove piping issues. Still trying, but looks like I might be sending back to Glock soon.
I had no experience with handguns and without discussing with anyone, bought a Smith 5904 9mm close to 25 years ago and that was no gun for a starter. Very first shot, I tore up my hand with the slide recoil and was amazed with the penetration thru a double 2" x 12" backstop. After only a few rounds (easily less than 500) the gun would rapid fire 2-3 rounds. Had a friend who had previously been a LEO and competition shooter, shoot the gun and the thing shot a triple on him with one trigger pull. Called Smith and the lady was quite nice and immediately sent me a mailing box and they replaced the slide and all was fine after that. However, I was never comfortable with that automatic and sold it and bought a Smith 14-4 and still have that gun.