I've been using the same keyboard for more than 10 years
Seriously, I don't remember exactly when I bought it, but I remember I paid around 150 USD at the time, when mechanical keyboards were only starting to become popular. I just know it's been more than 10 years and this thing is still trucking along fine.
It's a "gamer keyboard" even though I never used the gaming features and, despite the backlighting, it's not RGB, these colors can't be changed. It's still as smooth as a new keyboard, and I type at least 500k words a year in it for my job, not counting all the blabbering I do on the internet. I think the keycaps still look as good as new because they are white and black plastic molded together, so there's no paint to wear off.
I've been wanting to buy a new mechanical keyboard, with better ergonomics and maybe a detachable numpad, but at the same time it feels like a waste of money while this tank is still alive and kicking.
It's probably one of the best purchases I've made in my life.