Just like the way most of us want to invest and cash out immediately lol. But then, if we you are in a big project and you see a glaring future about it, it's good to invest and let it grow, not only short and quick investment only.
Few coins are cool for very long term investment, I agree with you. But there is nothing wrong with making quick gains on some trade setups, speaking from the angle of a price action trader.
Sometimes I see highly profitable setups with good R:R ratio and swing trade them for short term purpose. This doesn't mean I don't keep some coins for very long term.
Doesn't wrong but has a lot of risks. If you know that the recent exit scam, Sushi coin has a huge number of traders invest for the short term because of what you said. Many scam coins come to operate their scam by doing pump as high but must believable as they can, in a good reputation exchange then hola, guys like you drop into their scam in a heartbeat.