Games that force you to do handicapped things to get past something that you try to avoid so hard.
"Rage" Games which are basically youtuber bait at this point. They're not fun and unlike earlier flash games like N and N 2.0 they usually require no skill or timing at all, just trial and error.
Games which give out free stuff on a holiday. Basically loving useless stuff which everyone gets, which in games like tf2 usually forgets everything up (See Chicken Kiev, priced at 9 keys) or makes it so everyone is slightly dissapointed.
Games that force luck into everything. I'm talking about rust, NEO Scavenger, and Unturned. All three of those games require incredible luck and not much else, and they're all survival games so that makes it worse. Every loving time I die on rust or unturned I get so loving pissed because I was sniped by someone while hitting something against a tree. DayZ is an exception because you can't craft much at all so the only luck involved is finding your weapons, and as we all know even massive 21 gunned cigaretteoots can be toppled by a simple zombie horde when they decide to random sniper headshot a naked.
Games that do pixel art wrong. Pixel art is fine in my books as long as you don't do it piss poorly. Early terraria is the perfect example of this, and even though it has largely improved the early game just makes me want to puke from all the relics in it that just make it look like a scratch game.
Games that do retro music. Seriously, I want to loving shoot myself after hearing Day on terraria every single loving time I boot it up. I purposely go elsewhere because I don't want to listen to "bOP BEEP BEEP BOP BOP bop BEEP BOOP DA DA DA DAA DA... DUH DUH DUH DUH, DUN" on loop for 10 loving minutes.
Games which take Unity and loving drown it in assets. Unity in itself is a good engine but it gets a bad name because some egghead decided that he could cash in by simply stealing a bunch of unity assets off an asset leak and dumping them into his stuffty premade shell of a game.
I despise flash "games". Those games which you would see on your little sister's computer on some shady ass little girl's game site. Those types. I love the normal ones.
Games which use boobs as a way to persuade someone to buy it. I mean, what loving furry would have bought "GENDER BENDER DNA TWISTER EXTREME" if it wasnt about furries becoming loving girls? That's the main loving selling point. The tank dating sim on steam? Oh, they have boobs now so it's ok. This is the type of stuff I would actively avoid on newgrounds, the things with boobs in the main loving image.
Games which just penetrate you after a while. The games which just get boring and then say "forget you". Those types of games, the ones that we're previously fun but then the devs realised it gets boring near a point so they take a big fat stuff near that point.
Games where you don't know what to do. It can be done right, I was wandering around in HL2 the first time I played it but that's a proper game. Games where you have to wander around looking for an obscure objective are no-nos for me.