I think people exaggerate the dive into the abyss thing and risking it all. If you have some savings, you can try to launch a business and if it doesn't work you can always go back to work for someone else.
At a given point, someone is going to give you another job as a sysadmin again. He can even work remotely and easily make more than $400 a month.
If you are not hiring other people and purchasing equipment, starting a Saas business as a sole founder has minimal financial risk involved compared to almost all other types of businesses, it's really not that risky.
I think what holds a lot of people back is the fact that they come from an employee background probably at the family level, and they see the world through the eyes of an employee.
They don't even remotely consider the several options that they actually have available.