Because all their investors don't like day/short term traders and would yank all their money out of the fund if the fund manager was not an investor type. Try to start a hedge fund based on day trading and see how much trading capital comes your way.
Because short term traders are a bunch of uneducated gambling fools who usually bet the house and inevitably lose. And as little value in society that long term managers create, short term gamblers create even less. (Since they usually stay entirely out of anything that involves real *investment* and business creation. Long term managers inevitably have their hands in all sorts of pies.) Couldn't resist.
"I'm an INVESTOR, i don't do that quick in and out garbage" I don't care who likes it. My "garbage" makes more per account than their long-term "garbage." Tell them to kiss my ass while I take another distribution.
Where would very short term traders be without the leverage. I remember when commission costs were exorbitant. Say $100 minimum. How would a day trader operate with such costs. Times and the world changes. I guess a lot of mediocre traders can succeed with position trading where damn few mediocre day traders would succeed since the required skill level is so much higher, some adapt more quickly and some are unable to. I'm too damn old and slow to change. But I don't hate day traders. Don't envy them either. Different strokes for different folks. There is room for all, both the grunts and the over educated.
I question the whole premise of this topic, other than you thought it would stir up a debate. I see little evidence that longer term traders "hate" others. Each chooses their level
They "hate" day traders because if the word gets out that you don't need over paid money babysitters (aka managers) they will be out of a job. Anything that hurts their bottom line is wrong and the appropriate propaganda is disseminated accordingly to the sheeple. Now, not to say short term is for all, but these guys are raking in huge fees and they want to keep the scheme they have going!
So the "educated" fools from leh, BSC, MER, who took down the economy and are sending us into a recession are non-gambling geniuses? ooo i'll have to write that one down.