After a night of sex or other rowdy tomfoolery, a person would ask the person who was enjoying the sex, whether or not they where succesful, commonly used when a virginity is taken.
Whent he prefix Un is used, it shows a "Unsucsexful" night.
Dave: I heard you lost your V last night
Guy: True
Dave: Where you sucsexful?
Guy: TBH NO! i was unsucsexful.
It is said of the situation where a person has the bad luck to make contact with his testicles against an undefined surface or object, intentioned or not.
Given the nature of the word, it is more appropriate to design cases where the interaction is made with a moving object, for example, a ball.
Although it is extremely painful for the victim, it tends to be considerably funny to people who witness it.
Today in the baseball game the pitcher took a nutshot; the baseball hit him in the nuts.
Man, I just watched the funniest nutshot video ever.