Answer:
I'm assuming that a "1-8 spinner" is similar to an eight-sided die, so the probability of spinning a 10 is zero.
When throwing dice, or flipping a coin, etc., each outcome is independent. That is, it's not influenced by the previous outcome(s). So if you get three 8s in a row then the probability of getting an 8 on the fourth throw remains at 1/8. The probability of an 8 on each and every throw is always 1/8.