How much does luck play a part in success?

Recently, among close friends, we were discussing life goals, who has them and who doesn't... How it affects a person's lifestyle, their success... In the course of the discussion it turned out that many people have no goals, no what they are going forward for... So getting back to luck, it seems to me that if you're lucky, it motivates you to go forward, because you know that somebody up there is supporting you...