I'm not sure what he is referring to, but I would suggest narrowing your focus too much to make use of unanticipated opportunities (or even notice them, if you'

I'm not sure what he is referring to, but I would suggest narrowing your focus too much to make use of unanticipated opportunities (or even notice them, if you're narrow enough). As PG has repeatedly written, many successful startups end up changing direction at least once before they get a successful product.