I just don't like...
The Browning Hi-Power. It's a great gun, but that silly grip shape just does not fit my hand.
Most S&W autos. The only one I like at all is the 39. It's the only one close to fitting my hand and it has historical significance. The rest all have bad triggers and inconvenient controls.
SIG-Sauer autos. The slide is to high above the axis of the forearm and the controls are hideous.
Glocks. Can't really put my finger on it, but I just do not like them. The grips are too dang big in circumference, but even with that, I just do not like them. I think it's a rejection of plastic, mostly.
Colt Trooper revolvers. Bad trigger in double action mode and just ugly.
Colt Python revolvers. Bad double action trigger and rather delicate internal workings. Cool looking. Probably the coolest looking modern revolver made. Can't stand them.
All the crappy, cheap built, frowsy wannabe guns.
Beretta 92. The Brigadier was a really neat pistol with a goofy safety. Beretta double stacked the magazine, added a double action function and changed the safety to a hammer dropper. Four pound gun, quarter ounce bullet. It sucks.
Korth revolvers. All that money and hand fitting and the trigger sucks.