If the question is "given all other possible uses of my time, is this one the best use possible?", then the answer will be "no" for almost any given value of "this". A likely result is doing nothing while one waits for the "perfect" thing to do - it might not apply as much to people on news.yc, but this does describe many people I know.

If the question is "given all the ideas I have right now, and considering the effort to implement each, should I work on this?", the answer might be different.

In fact, it is impossible to determine the best possible use of your time without determining, without doubt, the meaning of life.

Did you ask yourself that before posting that comment?

People have different interpretations of what they consider meaningful.

Actually, I did ask myself that question (clearly, I'm not always listening to my own answers).

Re-reading what I wrote, it sounds harsher than I had intended. Here's what I was trying to get at: for me, most of the meaning in projects like this (IMO) lies in the interpretation of why the artist chose to do it at all. My own limit is not typically fear, but indecisiveness.