a hedge fund is an unregistered vehicle for pooling a great deal of other people's money together to pursue trading/investing strategies.
no other vehicle is as well suited to this purpose, with the exception of the mutual fund, which is registered, and an even mightier asset gathering vehicle, because they have the right to advertise.
ok - so what's the big deal you might ask, doesn't everybody know this?
well - if you read the definition carefully, you'll see that a hedge fund is a legal vechicle for gathering funds - many people claim to be good traders, but how many are both good traders and good asset gatherers?
sure - you can outsource the asset gatherer bit and hire a professional salesperson - but they'll take a big piece of your income, as much as 50% in the most egregious cases.
so - only if you have the ability to penetrate the industry of instutitional asset managers or the coterie of high net worth families in order to gather the assets does setting up a hedge fund vehicle make sense.
at the end of the day, it's your ability to generate a return on assets that matters. solo trading, hedge funds, prop firms, bank prop desk, CTA, investment club ....et al are just different vehicles with maximum asset size potentials and different profit sharing considerations.