One, because the market is still offering new opportunities and will not run out of ideas. Even though many projects are copycats and did not succeed, it is still interesting to find and be part of the development of this industry. Two, market cycles are real. Prices are spiked or dropping depends on what season does the market is in and the factors like news, laws, support from big institutions, adoption of crypto, etc.. Three, some alts did rise along with btc but there are coins that is independent to the price of btc. Their prices is more stable but also are more subject to price manipulation. Some even claim it is "centralized" crypto, which I find so ironic. Four, the market will never be stable. The fluctuations sure bring disaster but it also brought opportunities for many people. It's like playing with fire but once you get used to it, you won't feel the burn anymore.