Infomercials use similar temporal structures, but they are forced to use different endings because the whole thing is framed as something offered by the client.

Infomercials use similar temporal structures, but they are forced to use different endings because the whole thing is framed as something offered by the client. So they use the Client offering vast reduction ending. User, Expert, Expert, Client Discount! These methods surely have evolved to dovetail with psychological biases: New information leads to a tonic level of skepticism, which should be assuaged soon by expert assurance before it coagulates into general aversion for the product. Once this has been achieved, you can plug a specific product meeting this newly created cognitive shelf-space for a want.