Afaik most animals' nails/claws continue to grow but break off/wear away, like our hair continues to grow but falls out. Some animals even their teeth keep growing if they don't wear them down. My nails still grow a lot.. They just don't get long because they tear/break and I file them when they do. When I was doing Judo I had to cut them every day to keep them short.
If I protected my nails, and resisted the urge to peel them off then they would get long.
When they get a certain length they get like a pull-tab in the side, like a tear line, and I get an urge to tear it along the line.
The reason why the end of the nail is white is so that it's weaker than the rest of the nail, and has weak-lines in it so that if it breaks it just breaks along the lines of the white rather than breaking down your whole nail. That's why when I tear them they tear off neatly. I only tear them when they get weak and the tear line appears, along with the urge to tear it.
I said tear a lot of times.. I'm tired..
