I really don't believe the nail beneath should get damaged. I have been doing three nails on my right for a couple of years now - and last month I had broken one, so the nail-lady removed the fake one to replace it. The nail beneath was a hard and strong as ever, though just a bit scratched up. I have heard people say that the nails beneath fakes get soft, but I have seen in my own personal experience that it is not so. So I don't know if the "conventional wisdom" is wrong - or if I'm just lucky.