[jjxw]

Turns out most day traders are eaten alive. There's one study a few years ago that looked at Brazilian day traders and found 97% of traders that traded for more than 300 days were unprofitable [1]. I imagine this is due to a combination of factors which include 1) no real edge against the market and 2) fees. Of course unclear if their results generalize to other equity markets, but I think this is some evidence that the average day trader will have a difficult time beating the more sophisticated market participants over a large sample.

[1] https://papers.ssrn.com/sol3/papers.cfm?abstract_id=3423101