One real test to see if you're ready to be an entrepreneur is seeing if you would do a startup for 2 years, working 80+ hours with the emotional roller-coaster while knowing you would certainly fail. Personally, I would. I enjoy it way too much.
The difference is that this was at BigCo. Does this mean that I'm not cut out for a startup?
(EDIT: Am I a fool for believing that I can escape from 80-hour work weeks and emotional roller coasters by working at a startup?)
The thing that everyone seems to have forgotten is that large part of the 80 hours at a star up as a founder, is self driven. Ie you'll jump out of bed everyday excited to get to work. If you can make sure you don't get burnt out, I think it's sustainable at 40 hours a week.
Michael Wolfe has some great answers on quora about how to run a startup and not get burnt out.
But if a almost certain failure served a greater good that mattered to me, I guess that I'd be with you.
Failure is a concept with shades of grey, and largely depends on your definition of success. I've met a few people who from my perspective are amazingly successful who feel that they are failures.
Here, I have an optimistic view of failure, as in the startup has to close doors with a profitable exit. Even if the startup had a positive impact on customers and the world, I'd classify this as a failure (because of failure to sustain).
Perhaps this quote sums it up:
"I don't build in order to have clients, I have clients in order to build."
The startup is my client.
If the motivation comes from an innate desire to learn more about your market, your competitors, etc. then working on a startup begins to look more like academic field research and less like executing a viable business model.
Not to collapse into an argument over semantics, but the very core meaning of the startup concept absolutely rests on the will to survive no matter the odds, a strong desire to succeed and sustain itself as an entity that provides something of value to real customers.
If this is true, then the founders of the startup who got into it only to have a "powerful experience and greater knowledge" would, in essence, be going against the very nature and purpose of a startup.