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Disney World has a promotion offering tickets for half price on all rides for the day. John buys tickets for him and his girlfriend and imagines having a wonderful day. Although when he arrives as Disney world they have to spend an additional half and hour in queue at every ride because of the additional number of people in the park.
This wanted/unwanted expectation where the wanted has a direct relationship with the unwanted that follows it is called [...]
Sally spends 2 hours in the morning to make herself look beautiful as she want to impress the jocks at school. However she finds herself attracting the attention of not just the jocks but the geeks and when the geeks stare at her it makes her uncomfortable.
This postive/negative outcome where the negative the follows it has a mutual relationship with the preceding positive ...
The negative effect might also not be obvious to the original user who benefits as it could be another person who suffers the causal effect.
I can think of causal effect or symbiotic relationship but both sound to scientific for the above examples and the context of what I want to say.