When Bitcoin dropped to 76k, those who sold believed it would fall even further. It's easy to talk in hindsight after something has happened. Maybe Bitcoin would've gone lower, in that case those sellers would've been seen as making the right call. That outcome was a very real possibility. But it didn't happen, Bitcoin climbed back above 100k. In situations like this, I prefer holding steady over making frequent trades.
After all, not selling doesn't lead to much regret, but selling and then watching it go up hurts a lot more. That's why we see a lot of FOMO buy.
what you actually find is that its not the normal investors 'selling out' to just buy in lower. its not normal people the majority of the time panic selling..
its again alot of whales manipulating things
what they do is they use arbitrage, for instance the btc and eth markets
[BTC->USD] -> [USD->ETH] -> [ETH->BTC]
by doing this they dont have to wait hours or days hoping for lower prices to buy back in
instead whales quick arbitrage(in milliseconds) to cycle/rinse the 3 pairs, to get back to holding bitcoin again without causing much of a loss of their holdings.
they repeat this many times. causing alot of [BTC->USD] sell orders to be shown which cause the price to lower without them losing control of BTC holdings
in short they can repeat this trick hundreds of times with the same lump of coin
if it was an individual just selling to just exit with fiat.. or to wait for a lower price to buy again, you would see a delay in the other pairs and other exchanges of same pairs.. but because all other arbitrage path markets move simultaneously shows the value moving in arbritrage circles, not sat as fiat waiting