Quote from nonlinear5:
(5) The markets facilitate redistribution of wealth from one group of people to another group of people. If the total amount of money in the pool is the same (which it is, more or less), then whenever someone makes money, it means that someone lost money. In the process of money transfer, everyone pays commission, which is a rake. By definition, if you trade as well as the "average" trader, you lose money because of the constant drain in the form of commissions and other transaction costs. That's all there is to it.
The stock market isn't a zero-sum game because stocks aren't simply ONLY investments traded from one person to another.
Businesses inject money in via dividends/buybacks so wealth is constantly being created and so value is added overtime.
If you subtract all the injections by businesses then yes it can be considered zero-sum.
The context of the 95% statistic is too vague since it is unclear what exactly the pool of people is the 95% representing. Also, is the 5% meaning people who are consistently profitable trading or professional? Or merely people who don't lose it all? Or people who beat the market?
I think what is correct is... 5% of people who set out to try to consistently make money in the stock market actually succeed in becoming professional.
Regardless I'm sure the 5% is made up on the spot anyways. What matters is that its a very small percentage.