Determing things on the outcome of something unrelated.
Not sure how to explain this properly.
An example.could be if a scrunched up paper is thrown into a bin, then the day will be good. If it misses, you could then change the rules to say if the next three throws get in then it negates the one that missed and it will be a good day. Or, If a certain score on a mobile game is reached then the test will be passed.
Does that make sense?
Is this a thing most people do?