Nomination: The 8 Track Tape I'm sure there are ones worse than this, but I would have to nominate the 8 track tape (circa 1973-1977). The 8 track would actually break songs in half, so that you'd be listening to a song like Life in the Fast Lane from The Eagles, it would start to fade out in the middle, you'd have several seconds of silence as it switched tracks, and the song would fade back up to normal volume on the next track. Horrible idea! Plus they always messed up in the player. Honorable Mention- New Coke.
I think New Coke would have to be number one...considering how unanimously it was rejected and how quickly it was replaced by Coke Classic...then again it may been the smartest marketing move ever. I'll have to nominate Crocs