I shave (my face) in the shower daily, and I change my Mach 3 blades about two or three times a year. Not only do I not dry off the razor after I use it, it stays on the shampoo rack in my shower so that it gets wet when my wife and sons shower as well.
A package of eight Mach 3 blades are somewhat expensive, but that will last me for years so I don’t mind.