That's as good a way as any of describing it. The fact is that because probability is random, luck exists - we have times when strings of things go well and others when strings of things go wrong.
Probability says that someone will win the New Jersey Pick 6 once in four drawings. That it will happen to any one particular person is about one in 14 million. The guy it does happen to "got lucky" even though it was bound to happen to someone.
In any series of random events, it will be possible to find a string of outcomes that seems to defy probability taken on its own. If it is a string of favorable outcomes, it is perceived as "lucky". If it is a string of unfavorable outcomes, it is perceived as "unlucky". In the long run, they tend to balance out.
I have a friend who is very lucky. She always seems to win things. One time on a ski trip, we walked into a bar and the waitress handed us each a raffle ticket saying they were having a free drawing for a pair of skis. She won them. She once won $4000 in a slot machine in Atlantic City. She won a new laptop from some other drawing. She's always winning something. Does this mean anything beyond what can be explained by probability? No. She wins a lot of stuff because she is always entering drawings. I only hear about the ones she did win. But even if her winning streak is above what probability would dictate for the number of contests she enters, the fact is that random events are not uniformly distributed. Because of that, there are bound to be some people who win more often than others.
Get fifty thousand people to flip a coin a hundred times and the average of heads-up occurrences is going to be very close to 50%. For each person though, some are going to have a higher occurrence of heads than others. Some may be very high. For instance, tossing 70 or more heads out of a hundred flips will happen about once in 25,000 attempts, which means it's going to happen to two people, on average, in our example. If a head is seen as a favorable outcome (maybe they get a dollar for each head they throw and lose a dollar for each tail), these people will be seen as "lucky". But probability says it will happen to someone. Luck is when it happens to me.
Combine the confirmation bias with the fact that some people will win more often than others by sheer probability, and my friend's uncanny luck is explained. No black cats necessary.
