My worst decision on bitcoin when i bought bitcoin on high price then a couple of hours the price went down and as a result i panic and sell it even i will lose a lot of investment. That's a newbie mistake from the past and it happens long time ago but now i learn a lot from that.
I think nobody knows when bitcoin prices will go down. So it's a natural thing when you buy and then the price goes down. As is the case today. Many people are losing because the price drops very quickly
well you kinda can guess it because for example right now there was a huge bubble not a long time ago. Then the price dropped a little bit and right now it is coming back again. I can almost bet that it is going to go down right now to like 1500 dollars and I wouldn't be surprised at all. The price was going up way too much and too fast.