Generate income first then quit your job. If you don't have revenue coming from your products, you'll spend most of your time trying to do that. And note, that isn't coding or product development its advertising.

Before I started contracting I changed jobs to ease my work / life situation. Early finish at work and shorter commute allowed me to do side projects. After 1 year I'm now starting to launch some of the projects and still not generating revenue yet.

Set yourself goals and hit them, every month. Then quit.