Sometimes screw-ups turn out to be good. In an episode of The Simpsons, it was scripted that Homer would sing "I am so smart, I am so smart, S-M-A-R-T". But when Dan read it, he screwed up and said "I am so smart, I am so smart, S-M-R-T I mean, S-M-A-R-T". The editors liked the change so much that they kept it in and it is in the episode to this day. The line also appears in the video games The Simpsons: Hit and Run and The Simpsons: Road Rage.