CH blog post comment is so true (can't hard link to it):

    There is a fundamental difference in philosophy here.

    Some startups work 24/7 because they are “swinging for
    the fences” (to use a baseball analogy).

    Where other startups, like yourself [37signals] back in
    the day, are content with simply hitting “singles”.

    ....

    Here’s the philosophical difference, you can live a good
    life on hitting singles, but you’ll never become filthy
    rich unless you swing for the fences.