I'll answer your question another way.

If you're 14, work at it as hard as you can. When you get to 16, you might still have a shot. If you're older than that, you probably should stop trying to make it. The people spoken of above are very rare cases. People who actually GET into the NBA are already very rare cases. You need to have talent, a naturally good physique, hard work and guidance. When you're younger, you learn faster. I'm not trying to discourage anyone, I'm just trying to be realistic.

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SBT.