"Some of them will make millions of dollars each year "
And some will go broke...
And some will go broke...
Clearly a few will make millions, some will make enough and most will go broke, but that's the way business is.
Now, to some how figure out a product that people want and get the courage to quit my job ... not easy!
Not saying that it is wrong to quit your job, but doing so is no guarantee to become a millionaire. Why did he even write the "some of them making millions" line? It's dishonest, in my opinion (he probably didn't mean it like that, but it draws the wrong picture).
Also, will people be more employable after quitting their jobs? It depends what employers are looking for. Some of them want "stable" employees who won't go leaving soon again, when the next best opportunity shows up.
Yea I guess that is true. It gives you a lot of things to talk about in an interview though, and you will no doubt have polished your dev skills nicely.