In any market, it is normal to factor in the price increase or decrease, unless the change is too big to pay attention. Normal btc fluctuations are in the hundreds of dollars. It is also the chance for traders to make a profit. If btc decreases too low then you can process it depending on the situation. If btc is down but can increase quickly again then you can wait; Otherwise, you can sell your btc number, accept losses, and start another investment at a lower price,  making a profit to make up for the loss.