First off you should know what a Tradeoff is ok? So a tradeoff is basically a decision that places higher value on one of several competing options. When deciding what to include in your offer, you should look for Patterns that will help you realize what your best customers value, and focus on improving your offering for most of your best potential customers most of the time.
Aversive conditioning is the use of something unpleasant to stop unwanted behavior. The client knows that outside the therapist's office, the food will not induce nausea.