Syndicate, what a terrible game.

Resistance 2 and infamous 2, though the latter one is a worth title to play, just not along the line of first one.

fable 2 to fable 3

Pretty much every sequel to an N64 entry of a franchise:

Super Mario 64 > Super Mario Sunshine
Zelda Majora's Mask > Zelda Wind Waker
Mario Kart 64 > Mario Kart Double Dash
Star Fox 64 > Star Fox Adventures
GoldenEye > whatever Bond game came after
Banjo Tooie > Banjo what's-it's-name
and more.

Also, on a more serious note:

Star Wars Knights of the Old Republic > Knights of the Old Republic II: The Sith Lords

Crysis 2. I uninstalled it before I even finished the game. The story was boring. No mention of Nomad. And profit dies in the beginning. The reason why I bought the second game was to find out what happens to those two. Thanks a lot. Never bothering with 3.