Please vote the right one to help beginners.
It shouldn't be only one or the other. One of the most valuable things I learned investing in cryptocurrencies is to diversify holdings and develop a portfolio rather than going all in on one coin. Start doing significant research. The more diversified, the better, but always hold some bitcoin -- never go full shitcoin. Also, try to start recognizing the market cycles: alts go through "seasons." During alt seasons, everything pumps. During BTC season, 90-100% of alts dump. This is the sort of baseline analysis to consider when rebalancing your portfolio.
When you go all in on one coin, you often develop a "chasing" mentality. You see other markets moving, but your position is stagnant or bleeding. So you liquidate and buy another coin. But it turns out you bought the top, and now you've instantly lost half your money. This is what it means to be a "chaser."
It's better to buy dips and hold dip buys in your portfolio rather than to chase pumps. That much, I can tell you.