These are two simple questions that people often fail to ask themselves. Not in the "video games and have-sex-all-day" sense, but rather in terms of how you will build a sustainable lifestyle that fits in with your goals while pursuing something that both stimulates you and you are relatively "good" at.
Sometimes, you cannot work on either of these things enough. If what you want to do is to be a professional athlete, or to win a gold medal, you can put in as much work as humanly possible and still not have the natural talent to succeed. Conversely, you might be the best bean-counter in the world, but if counting beans isn't your passion, you will likely wake up someday relatively secure, but regretting that you failed to "take your shot" at what you really wanted to do.
There is one simple truth that I have found through the course of trying to improve my life:
It is generally much easier to change what you are good at than what you want to do.
Again, this has its limits. It's tough to be good enough at math and science and have enough dumb luck to become an astronaut. However, if you identify what you really want to do with your life, it becomes easier to take affirmative steps in that direction. Maybe you won't end up being an astronaut, but why not take your shot? Surely the skills you learn along the way will help you find some kind of related employment, especially as the private space industry starts to take off.
Changing your dreams, on the other hand, generally involves a major life event or change in circumstances. Generally, you do not have any control over these. Otherwise, changing your dreams to be the best bean-counter is, for lack of a better word, "settling." And though it may be fine to settle when you have a family to care for and a lot of bills coming in each month, by no means is it necessary. It is possible to make money doing whatever you want—you just have to be willing to improve what you're "good" at.
Dr. Ronald Mallett wrote an excellent book titled Time Traveler, detailing the loss of his father at an early age, and his subsequent dream to build a time machine to go back in time and meet his dad "before" he died. Mallett grew up fairly poor, and was not a natural at the advanced physics and math that he would ultimately master. But he took a job as a night watchman so that he could study the concepts for hours upon hours, generally uninterrupted, until he was able to understand them at a PhD-level. He recently has published his idea of using focusing lasers to bend space-time in such a manner so as to create a wormhole, but that's a story for another day.
Will Mallett ever actually build his time machine? I have no idea. The point is, through sheer force of will and hard work, Mallett forced himself toward an "impossible" goal, and has actually made substantial progress toward it. He identified what he wanted to do, and eventually became "good" at it. Why don't more people do this? Again, another story for another day. For now, take a moment to figure out what your true goals are in life. Even go so far as to make a "life plan" for the next five years, or a "bucket list." Then, identify concrete goals and timelines for completing those goals along the way. Even Ron Mallett has made progress on his time machine. You're telling me you can't make progress toward writing that book or becoming an artist?
Sit at your keyboard or pick up a pen and paper and get started.
Questions? Comments? E-mail D.J. at firstname.lastname@example.org.