There are some things you really only need one of, so why clutter up your life with multiples?
Are you actually the kind of person who ever uses a multi-head screwdriver in each hand? And while I understand an extra can opener in the emergency kit, do you really need three in the kitchen drawer? Come on. You aren't on the moon; there's a store nearby where you can get another if this one breaks.
Keep the best one and get rid of the inferiors.
For some things – corkscrews, for example – it's worth having one spare so an evening isn't ruined by a broken tool. (But if there's a corkscrew on your swiss army knife, as there is on mine, you've got your emergency backup, so get rid of the big extras).