Fridge Brilliance In the remake, The Devil shows up after Elliot lusts for someone else's woman. A violation of one of the Ten Commandments.
If I recall correctly, Elliot mentions at the beginning of the film that Alison's recently broken up with her boyfriend. She's back together with her boyfriend at the end because of Elliot's own wish that she have a happy life.
Fridge Horror: In the remake, the escape clause has made me wonder. If it requires a selfless wish, then no one who has read and understood the contract could escape it. Think on it, a person who knows they need to be selfless will be looking for a way to help themselves in the long run. They are out to save themselves and that is not selfless. Thus anyone who tries to understand the full extent of the deal ends up losing the only escape clause.
It could probably work if the selfless act was spontaneous.
Fridge Logic: In his review, Roger Ebert questions why the devil goes out of her way to be a Jackass Genie, causing Elliot to want out of the deal. Wouldn't it be better for her to genuinely make his life wonderful, so he will recommend her services to others? Arguably applies to the original film as well, but there the devil had a concrete goal and doesn't need to keep drumming up new business in perpetuity.
Evil Is Petty probably. Also the ending suggests she's not that bothered with losing the soul in the end.
She's trying to make him use up the wishes as quickly as possible, so that she can get his soul.