I'm in the process of reading Seth Godin's book What to do When It's Your Turn (And It's Always Your Turn). It's not a book that you sit down and read all at once. The book is written as a series of short pieces, all of which fit together and move toward the central theme. But each piece is meaty and thought-provoking, and must be contemplated and savored before moving on to the next.
The central premise of the book is essentially that NOW is the time to step up to the plate and do that thing that is inside of us that might not work, but which we think is worth doing. The book includes a piece entitled "When is the right time?," which I thought was beautifully written. He writes of a talk he gave to a small group of youg, privileged interns at an investment bank. He was advising them about "their freedom, about how they could choose to do their very best work, to become more than a cog in a (profitable) machine," when one of the women raised her hand and made the point that with their student loans, it made sense to hold off, to wait to take risks and find their own paths in life when they are at a point when they are better established.
He writes that it is never the "right time," and says
We have a thousand perfect reasons to give up our freedom in exchange for the illusion of safety. All of them are based on a misunderstanding of fear vs. freedom. This is the chance of a lifetime, our lifetime. Not someone else, us. Not later. Now.
P.S. I have probably mentioned before, but I read Seth almost daily, and generally find his short pieces to be deeply profound. I highly recommend his blog, and the book, as well as his podcast, although truth be told, I don't like the podcast as much as the blog or the book.