Better leverage what you have.
A young person, who has entered workforce, may lack in experience but has the advantage of an open mind, low-maintenance lifestyle, and high energy levels. Young age is the right time for creating a solid foundation for future. I have written about benefits of starting early.
Many students wait to work on their startups till they graduate. Not a great idea. While in school, students have access to library, labs and do not have many things to take care of. It is also easy to maintain focus in such a situation.
If you are a student, you can reach out to seniors and teachers and seek suggestions. You have a community ready to test your ideas. Facebook, Yahoo, Google — these three started either in a university lab or in a dorm. There is a reason for it. There are many student-only business plan competitions; take advantages of these while you are in school.
If you are between jobs (out of choice or forced) you will have lots of time of your hands. Utilize this time to read, learn about yourself and what you really want to do. It is better to do something close to your heart than jump from job to job.
Somebody who is in a job is also not at total loss. Many people who are in job crib about lack of time to pursue what they love; but a job also brings opportunity to learn and make an impact if you look hard and close enough. You can become a better hacker and more effective socially, depending on the nature of the job. It is also easy to develop a network while you are working. Working 4×4 and working on a parallel path may be for you if you are currently in a job.
So your potential need not be limited by your current situation.
Thinking about what you could have done if you were in a different situation will not take you anywhere. Taking action and leveraging what you have, will get you started and take you ahead.