My worst experienced is I did not sell any my crypto in the end of 2017, because iam too greedy and just hope the price will keep going up until my asset reach amillion dolar. Learn from that mistake, in this bull cycle when i made good profit I always sell it by half amount.
I have the same experience, I would say it's the worst but I would also like to thank that situation as I still made money overall. I just regret I did not sell everything, I could have made a bigger than what I made that time. After 2017, I slowly spend my asset and I was not able to fully ride on the new bull run that happens late last year until this year, and I have a little regret with that, but I'll continue saving now.