My theory is that people buy it as holiday gifts.
I can't think of any other reasons why but probably that is the most common answer you will get here since Bitcoin is always on a downtrend every Christmas holiday in December. Now, the real question is when would Bitcoin start to push its trend upward so that a bull run would start as soon as possible?
I think it happened yesterday when before Christmas prices went up and people felt it was their Christmas gift. I also got yesterday's profit when the price went up I was very happy for that