Because you are only interested in making more $$$$. Bitcoin is bigger than fiat, it's the only coin that could survive a government attack, the only one that would skyrocket when fiat crashes and so on.
"Cashing out" only means you are losing money in the long term:
So you are cashing out in a coin that keeps crashing vs holding a coin that keeps going up (Bitcoin).
If you only care about making a quick dollar buck then do gambling with any shitcoin you want, but the point of Bitcoin is not to buy and sell it for more dollars. Bitcoin has value because it is decentralized, if it was centralized it would be worthless.