Entrepreneurship and office jobs can be compared with short and long term investment. When you work in office you get paid/income/profit instantly (basically weekly or monthly), but if you start your own business, you can wait for your first real income for ages. Similar to investment, to start your own business, you must do market research. If you are not experienced with that, lazy, or simply dont want to spend time on it, then the you are gonna work for have already done it for you.
That depends on the type of business you would like to do, you may not end up waiting for ages. I used to have this affiliate website that basically redirected people to crypto websites they wanted. It was a list basically, if you want exchanges there were list of exchanges, if you wanted casinos there were list of casinos, if you wanted services there were list of services, cloud mining, physical mining equipment etc etc etc, it was a list website basically and this was back in 2014-15, so it was an old thing.
There, I started making money right off the bat, didn't take me longer than 10 days to start earning money, but I earned very very little, nothing big, like 20 bucks per week, so I stopped after a while.