Hindsight is always 20/20 even in the crypto space!

Following up on the opposite end of the spectrum from my post taking a vote on the best crypto currency move you have made with this one. What is the biggest fail you have had in the crypto space? I know getting started I made quite a few and they covered different areas.
Some of my mistakes included things like:
- Overtrading and losing money on transaction fees.
- Getting hasty and not holding coins and instead trading a portion of a coin to buy another only to have the first coin go up in price.
- And my biggest fail, not getting into bitcoin and other crypto currencies when I heard about them a long time ago!
At least we can all learn together!
The main goal of this post isn't to shame or put down but rather to look back and learn as a community through mistakes of others and maybe even to laugh a bit at some of the things we have done. Also if you haven't put your biggest triumph on the other post head over and post it here.
Thanks again for reading and your comments, upvotes and follows!

Bitcoin 1KM5MaPNsZdAA6W3MQZQa2yqq1VzxV69My
Ethereum 0x79B4fAEAA31EAc19f33A1517288abE82cB2da6Fd