While luck is a *factor*, it's not the most important aspect. People who work hard and are passionate about what they do can increase their chances of "luck" in being discovered or knowing the right people, because they will work hard to get out there and meet people related in the field, or actively talk about what they do with others. Basically, hard work takes into account of "luck" in a sense that you can increase your "luck" that way.
As for talent, it's certainly there but don't take it that a person isn't "meant" for anything... Some people pick up things a lot easier than others, but imho with enough hard work, you can overcome a lot of challenges. I admit that there are times when there's limitations by birth... but most people blame their own lack of success on this way too soon (especially say, high school math >_>)