in my opinion, this is what happening right now as the trend of bitcoin price has been sky rocketing. what do you think affects the price increase of bitcoin today?
Mostly speculation. People are buying bitcoins and expecting to make money when they sell at a higher price.
And the danger in this is that it works until it doesn't.
If the only reason to buy bitcoin is to try and sell it to someone else later at a higher price, eventually one of two things happens: 1) you eventually run out of people to sell to because everyone already owns bitcoin, and with no future people to sell to, the price crashes because nobody can make a profit by holding any more; or 2) people realize that scenario one is inevitable and stop buying before everyone owns bitcoin, because the realization that the only way to make money on it is by selling it to someone else at a higher price is an investment structure that is shaped like a pyramid scheme (albeit unintentionally, but unsustainable nonetheless), and the price crashes.
Either way, it seems a price crash is inevitable because Bitcoin's utility as a speculative asset comes to a definite end, and there isn't now, and likely won't be in the future, enough utility in any other use case to maintain the price.
The price has fallen quite far. I'm highlighting the above quote because it's still true. The market has been intensely irrational and people's expectations have been irrational. A stable price is a far more useful attribute than a Bitcoin that fluctuates wildly, or drops from 19,000 to 12,000 in a week but sometimes also goes up that much too. That type of volatility makes it useless, and utility ultimately will determine value once the mania runs out. But the reason so many people are buying is because of the mania, and because they think you can get rich; that Bitcoin can't drop permanently. Read these boards, everyone seems to think any drop is temporary.
That's not how anything works. Anyone who says "Bitcoin is risky, but anytime it goes down is just an opportunity to buy more" is not recognizing the first thing they said: THAT BITCOIN IS RISKY. It's not risky because sometimes it can go down, it's risky because it can go down
and never go back up. If you don't accept that as a possibility, or better yet, as a likelihood, then you shouldn't be buying Bitcoin.