They are not, but think of it like learning to play a guitar: at first, the strings cut into your fingers, but then you build up enough calluses and playing it

They are not, but think of it like learning to play a guitar: at first, the strings cut into your fingers, but then you build up enough calluses and playing it stops hurting. Or, consider a building code: every rule was written in blood, and new buildings get safer over time.