I think you might have it backward. Luck here implies starting with exactly the same work ethic and abilities as millions of other people that all hope to one day see their numbers come up in the lottery of limited opportunities. It's not to say that successful people start off as lazy slackers as you say, but if you were to observe one such lazy slacker who's made a half-assed effort at building something that even just accidentally turned out to be a success, you might see that rare modicum of validation fuel them enough that the motivation transforms them into a workhorse. Often time, when the biography is written, lines are slightly redrawn to project the post-success persona back a few years pre-success. A completely different recounting of history thus ensues. Usually one where there was blood, sweat, and fire involved to get to that first ticket.