Dear foodfan,
Many Chefs do want to open their own place, but a few challenges stand in their way:
1) Start-up capital. Depending on the place they want to open up, start up costs can be anywhere from $50,000.00 to 2- and up million. Where does this money come from? Financial institutions are loathe to lend to hospitality businesses, as the failure rate is very, very high. The chefs and restauranteurs with an established track record have an easier time getting loans, but it's kind of a catch 22 situation.
2) Competition. Is cut throat. The public are fickle and will jump around. Just because you have good food and good service does not guarantee you a good business. Location is very, very, important, and good locations cost mega-bucks in rent, and usually have greedy and conniving landlords.
3) Partnerships. A good restaurant needs at least two partners, better three, working partners. Obviously the chef is one, and this is a full,(80-100 hrs /week) job. The Maitre D' is another, who works just as much as the chef. Someone good at marketing, web design , and public media is a bonus. Finding a business partner is like finding a spouse, you don't pull someone off the street and trust them with banking information, staff, or suppliers credit. The best partnerships are husband/wife, or people who have worked with each other at different places for years.
4) The first year. Will not make any money. If lucky, you will cover costs and maybe, just maybe, pay down some of the debt, but profits don't come in for at least two or three years later. Partners will not get a salary and hopefully can continue with their standard of living for the first year or so. The first year is a matter of having deep enough pockets to survive.
I hope this provides some insight into the wonderfull, glamorous, restaurant business