There are many games out there I've endured for only a smidgen. Let's see if I can remember some of them...
Shin Megami Tensei: Persona 3 FES
Resonance of Fate
White Knight Chronicles International
Harvest Moon: Back to Nature
Prince of Persia (2008 edition)
Scott Pilgrim vs. the World
Payday: The Heist
The Elder Scrolls V: Skyrim
Tomb Raider: Underworld
Far Cry 2
The reasons for not fully exploring these games and more would include everything from not having enough time, to being too hard, to the game itself not being as enjoyable as initially thought. Vanquish is a recent example of a very lame game I'm having a tough time seeing myself getting into.
Well I won't list my PC games because I have about 500 on Steam and haven't even played half.
So strictly going by my non PS+/freebie games, I've bought FF7 and Sly Cooper IV for Vita and haven't even touched either (I did download/install FF7, but SC4 is an unopened physical copy).
The Top Five First-Party Vita Exclusives That Have to Happen
The Top Five Third-Party Vita Exclusives That Have to Happen
Mortal Kombat vs DC
MLB 12 The Show
And a copy of Tomb Raider (2013) I have yet to open
Imperator Danknovaxperaux Divi filius Imp XIII Pont Max Trib Pot XLIX Cos CXVI Primus Signiferi Box-xy Princeps Moderatores Pater Forum
I have a lot of games I haven't even played . Just looking at PS3 games I have played but not much:
The House of the Dead: Overkill - Extended Cut
Tom Clancy's Endwar
Two Worlds II VELVET Game of the Year Edition
White Knight Chronicles (and I haven't played the sequel).