Depends on the game/reward/content/ownership
I tend to full clear Donkey Kong Country, Metroids, Marios, Smash, Zeldas. I'm a fan of sequence breaking, too. Speed runs are more enjoyable to watch than do imo. For games like Starcraft or Diablo I typically play them to death until I feel like I've "beaten it" ...which may explain my competitiveness in fighter & rts games. I'm not interested in full comboing/clearing/perfecting Ikaruga/I Wanna be the Guy/DDR tho.
Edit: How could I forget Dragon Warrior 3? I played that on my GBA sooooo much.