I think there are two condition. When you are a daily trader, you have to study the chart carefully. in here you can use buy when the price cheap and sell in the good price. Today, seeing the market that the major coin all in dump, so the time for buying is ok. But please choose the coin that have long term function like Etherium, Bitcoin, and other coin that have good program at future.
You are correct on your point dailly traders does those things, for me i prefer long term because it's stress free. I consider my passive income from those continues bounty campaign participation. While holding longer on good coins, i am still having some income from bounties which is i think good enough for a living.