Because I prefer wealth. Imagine cashing out of Apple or Google after it 2xed after IPO.
Here's a more nuanced response:
1) I honestly believe in the technology, and also believe there's much more room for it to grow. I'm even putting more in every month. I'm especially optimistic with smart contracts on the blockchain, i.e., ethereum + other smart contract L1s. I went through the process of a HELOC last year. It took me over a month to get access to those funds. In the ethereum platform, I can take a 50% LTV loan on my holdings in 5 minutes without any personal information being given out. Plus, mainstream fintech companies are exploring this space deeply (Visa, Mastercard, Paypal, Stripe, Square, Robinhood, Shopify, Fidelity, plus much more).
2) I don't need to. I live more than comfortably with my family's current earnings outside of crypto. Plus, if I really need to, I could take an aforementioned loan out to "cash out".