Good return is only the reason to invest in equity share. Market investment can get you huge return that is otherwise impossible from any other source of investment provided you have invested at the right stocks. There are instances where investors have gained manifold within short period of time by investing in certain stocks.

The price of each share could go up and/or to get dividend checks.

Plus it's cool to own a successful company, even at 0.00000001%.

Most do it to make money - for retirement, for a new house, etc.