Assassins Creed 3 - Online trophies. Never liked the MP mode in AC games
Battlefield 3 - Reaching rank 45 was a total grind and time sink for me after I had lost interest in playing this game when my friends moved on.
Battlefield Bad Company 1 - 10,000 kills online. No thanks!
Blazblue Continuum Shift - Lost interest and sold the game.
Call of Duty classic - Difficulty trophies don't stack. Not playing it through 3 times. Once is enough.
Call of Duty Black Ops 2 - The other CoD game on PS3 I don't have the platinum on. This is when Treyarch started making their games have stupid convoluted Easter eggs as part of trophy requirements.
Dead or alive 5 - 1000 fights online. No thanks.
FFX III - By chapter 11 and over 45 hours of gameplay, I was bored of this game.
GOW III - Had to force myself to finish this game. Not interested in going back.
GTA IV - offline 100%. Reaching level 10 and AWP trophies stopped from earning the plat. Likely not going back.
GTA V - One online trophy rendered unobtainable now.
GRID Autosport -Online trophies are garbage. A shame because I had gotten GRID 2 platinum before.
Killzone 3 - Server closure
Mortal Kombat - "My Kung-Fu is stronger" is a massive and unnecessary time sink. No thanks!
Persona 4 Arena Ultimax - Online is dead now.
RAGE - Remember being stuck on the last part of the game. Never going back.
Resistance 2 - My most heartbreaking trophy. Just needed 10,000 kills to get the platinum. Server closed.
Sonic Unleashed - Couldn't complete the final level let alone go for the remaining trophies.
The King of fighters XII - Online dead.
The King of fighters XIII - Online dead.
Tomb Raider - Online dead.
Bonus - Not a platinum but I forever will be locked out of 100% on Ridge Racer Driftopia. It was a game I got into the beta before it got cancelled. For some odd reason the beta allowed you to get trophies.