I think he was bad in both movies. I don't like how he plays Peter. He is too cocky and hipster acting. Plus, even before he became Spidey, Garfield's Parker was listening to headphones and skateboarding through school halls even when he told not to.
The skateboarding part especially gave off the vibe he was something of a "rule breaker." that coupled with what he did to gain access to Oscorp ( stole another kid's identity which got that kid arrested then trespassed in the spider lab ).
The more cocky, rebellious, "invincible" attitude should come AFTER he gets his powers and before Uncle Ben dies.
Also, I never once bought this Peter as a geeky science nerd. not saying you have to go all out dorky, but there should be a transformation ( physically and attitude wise ) from the meek, timid, nerdy straight A student to a kid who suddenly has godlike powers who feels he can do anything.
This Peter also came across as a bit of a selfish and self centered jerk where he expects everything to revolve around him ( especially in TASM ). Not in a mean spirited away, but he just didn't come across as though he cared about others aside from Gwen. Look how he interacted with Uncle Ben and Aunt May ( in both films ). He was somewhat "cold" to both of them.
and don't get me started on the height. TASM Peter just felt a bit too tall for the role. it's hard to buy him as the underdog nerd who constantly gets picked on my the big jocks when he's pretty much the same height as said jocks.
Paraphrasing X-Knight's great post here but it says what I feel well.
I will not miss Andrew Garfield as Peter.