I believe that trading is also about luck A successful short trade can only be done if the price of bitcoin increased shortly after you bought them. For example, the people that bought bitcoins before the price went up to 1,100$ after just a couple of days. They didn't study anything at all. They just got lucky that at the time they bought their coins the price went up dramatically. You can say that the timing was good or something but it's actually just luck since you don't know when exactly would the price of bitcoin go up.

But since not all of us gets lucky like this, most of us end up holding bitcoins for a long time even when some of us really wanted to just do some short trade and then exit the scene with their profit.