Probability:
A. the relative possibility that an event will occur, as expressed by the ratio of the number of actual occurrences to the total number of possible occurrences.
B. the relative frequency with which an event occurs or is likely to occur.
Luck:
good fortune; advantage or success, considered as the result of chance
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Even if something has a %99.99 chance of happening, there is still a chance for it not to happen. You can count cards in blackjack and come out ahead in the long run. You can also count cards in blackjack and lose a hand, multiple hands, or even lots of hands. The PROBABILITY is low, but sometimes random chance (luck) can work for or against someone.
In poker, there is a set probability you will get any particular hand. Just like there is a set probability you will get certain cards in blackjack. One is more predictable than the other, but both are not predictable with 100% success.
Carrion Fields is similar. Lot's of knowledge can increase your probability for success, but even with everything in your favor, there is a chance you can lose.
You can know everything about your opponent in starcraft. You can't forsee his every move. All warfare requires some luck in guessing your opponent's moves. You can be 99% certain he has used a particular build plan, but you can't know until you see.
Just like CF. All of these things are easier to be successful at with skill. The skill comes from knowing your probabilities, planning accordingly, and hoping luck doesn't fuck you over.
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