It depends. Usually day trading is more popular and for me, it takes 1/2 days to compete a trading base on altcoin circumstances. There are many altcoins what newly launched and sometime if you see that your project is getting pump continuously then i don't found any necessary to close your trade? Rather let it expand some more days right? I think this is how things works. But as crypto market is volatile, that's why can't execute trade for long and most of the time day trading perform better
The only time I might see day trading as a task is when I want to liquidate my coins and have to spot trade inorder to find a buyer. Besides this, long term investment in BTC is worth giving a try when there's a good DCA strategy to follow and being disciplined enough about doing so.