> If the market always knows best then why do I need traders except for market making purposes? You may not. It doesn't follow that the market doesn't. Long te

> If the market always knows best then why do I need traders except for market making purposes? You may not. It doesn't follow that the market doesn't. Long term US stock investment isn't the only reason people use capital markets. And even for passive etfs, your counterpart is likely hedging their exposure with someone who you didn't buy the etf from.