I discovered bitcoin when it was about $5 per coin and during that time for several reasons I could not buy it. I discovered eth and xmr when they were around $10 per coin and I could not find a good place to buy them. I discovered netko when it was about $0.05 and I could not get the wallet compiled. I probably had around 40 bitcoins and cashed them all out under $800 and I could name more.
You?
The biggest regrets is not buying when the price of bitcoins was too low in the past and in trading I have a regret that I didn't sell my altcoins at the right time when it was giving me good profits as I waited longer but price went in negative direction which gave me huge loss.