I'll add some weirdness to this discussion. The nails on my left grow three times as fast as the nails on my right hand. They also gow in harder and stronger. These are the nails I have to cut away so I can play fretted instruments.
Why do they growso fast? These are the fingers I injured with the saw. The Doctor said its a phenomenon that he sees from time to time but is unable to explain it. Hand injuries are full of stuff like this. Nerves that remain dormant for years then fire off for no reason. Sudden nail growth. More hair on the back of the hand.(Well that could be a different reason.)
If you like playing with strong fingernails that grow to a playable length in a week. Cut your fingers off with a Makita Table saw and have a Doctor sew them back on for you. Cost about $90,000.00 Or maybe learn to use finger picks, gotta be cheaper.