Yes, you "may" be able to get 10-12% return and be very liquid, or you "may" not.
A more realistic number over the long term is 7-8% return. The S&P500 got 8% from 1950-current assuming you reinvested all dividends.
Leverage is easily one of the best parts about real estate, but some people don't like the associated risk of being multiple hundreds of thousands in debt. For them, all cash financing is a better alternative as it is very safe, but comes with the tradeoff of lower returns. But even ignoring the money side of it, cash in full real estate offers another benefit. Real estate is REAL! By that I mean you can touch it, feel it, kick it. It is a tangible object that is intrinsically valuable that you and only you can dictate what happens with it. If you want to buy it under value, then you can do that. If you want to renovate, and raise rents then you can do that too. You control your investment, as much or little (property managers) as you want. With stocks you are at the mercy of the board of directors and have no input on how the company is ran. You often get poor information about their prospective incomes, and by the time real information comes out, the stock price has already adjusted near instantly.
But even full cash real estate can often beat the stock market, or at least match it. Assuming you buy using the 1% rule, your mortgage should be 50% of your expenses. But in this case you don't have a mortgage so your income is 1% monthly, and .5% expenses. Over the course of a year that is 6%+ return, plus ~3% inflation.