If it were worth a lot of money some day, you probably wouldn't sell it.
You'd just have a knife worth a lot of money sitting in a drawer.
To me a knife was made to use. I get the collectability thing and
not wanting to mess one up, so it's always the owners decision.
I have a Massad Ayoob Sprint that I am quite fond of. I carry it as a self
defense knife, which to me means that I don't use it for anything other than
self defense. The blade is always super sharp and ready. If the knife gets
a little banged up here and there, well that's ok.