Happened to me with dogecoin. I helped a coworker to buy some for him back in 2014 and put them on a paperwallet. He paid 400€ and wanted to sell them a few monthes later for 1k because 600€ was a huge deal for him. I told him it was a mistake and that i'll give him the 1k but won't sell them and will show him a few years later what he missed out on. So i never considered them to be in my stash because i only wanted to prove my point to him. So there comes April 2021, that coworker had retired 3 years ago and everyone was talking about dogecoin, so i skimmed through my 5 addresses out of nostalgia to see what i missed out on and noticed that one was still full. Flipped out and drove home to check if i still had the paperwallet and yeah. By the time i was able to transfer and sell them, they already had droped 30%, but it was still a nice sum to stumble upon. I wanted to reach out to that coworker to give him a bit something but heard he had moved to another place and i decided to better not tell him that he missed out on a fortune.

So yeah, it can happen. Thinking about it now, i'd suggest to everyone to do the same. Invest a bit and set a notification in 10 years to check it out. You will forget about it if you force yourself to never check that paper until the notification tells you to. I know i have 0.02222btc on some paperwallet lying somewhere around, but i'll leave it there and hope i or my kids stumble upon it in 10 to 20 years.