That was very bad time for me, when i sold out my Bitcoin. When bitcoin price was 9k+ usd, then i sold out my all Holding Satoshi for my personal problem. But now current price of per Bitcoin is 41k+ usd.
Everyone needs money at some point and if you needed to cash out at that moment, this is none of your fault. You can call it your fate.
However there are people who sell bitcoin thinking it will go to zero. Then there are other people who sell at 20K or 30K thinking this is the top. I feel sorry for those people as they do not have the proper vision.