• Your long term storage wallet needs to be in your physical posession.  Do not leave coins long-term in an exchange.
• Move all of your coins out of an exchange the instant they start delaying withdrawals.
• Losing your coins because you've forgotten your wallet password or lost the wallet.dat is incredibly common.
  
  • You won't remember that passkey in 3 years, and neither will the executor of your estate.
  • Put a copy of your wallet and instructions on how to access it with your important papers.

I started mining when BTC was under a dollar, and I remember buying some coins too.  I can't find those coins.  Did I spend them?  I don't know.

(I did find the one cascasius physical bitcoin I bought; so it's not all bad.   )