It not just depends on whether you're ready or not but also on whether your family is okay with you staying with them. You could be 30 and unwilling to move out but if your parents want you to, you should.
Family is the basic unit of community. In ancient times, human survival depended on preservation of close-knit units (joint family system and tribal affiliation). Individual identity was derived from the community and severe punitive measures were taken against social heretics. However, now that humans have found ways to artificially enhance fitness (Examples: Guns & Genetic Engineering), identity is independently derived and self has become superior to the community for a lot of people.
Societies that still follow such traditions are considered 'primitive' and others are called 'modern'. The world's witnessing a transition from primitiveness to modernity. According to some sociologists, excess modernization / individualism is bad and would eventually result in anarchy.
I'm 20, Indian and don't stay with my parents. Unfortunately / fortunately, I'm very attached to them and intend to move back after a few months. Marriage won't change things.