Running a business is like investing in stocks
With stock investing, you're thinking about where to invest your money.
As a business owner, you're thinking about where to invest your time (and your money).
Which new project to take on, which new department to build out, which new product to develop, which new marketing channel to set up.
These business opportunities are like stocks.
As an investor, you choose a stock because you think it will be a good investment.
You look at the financials, read the news, talk to other investors, and then you make a decision.
Ideal situation: you can buy a stock for $1 and sell it for $2.
It's the same thing with choosing where to invest your time/money in your business, except that the market isn't as liquid, so you can't sell off parts of your business whenever you want. The value accrues over time and, if you've made good investments along the way, you sell the business for a lump sum that's greater than all the time/money you put into it.
I was a business owner for about 20 years before I became interested in stocks, and boy howdy did they ever become interesting after I read all of Buffett's letters to shareholders. Someone clued me in to this connection about 10 years ago, and it took me a minute to dive in, but I really did.