Protons were shoddily built - they only have a half-life of 100,000,000,000,000,000,000,000,000,000,000,000 years...
Are you sure you're not thinking of neutrons? They only last about fifteen minutes if you don't put them in a safe place. And don't be too hard on them; it's the glue. We didn't have much to work with back then.
Actually protons are pretty hardy little critters. I haven't had to get a replacement supply yet. By the way, that half-life calculation is the lower limit.