Rebate pop ups

They are annoying because they are displayed to every user with the same discount, which means you lose margins. They cannot match the amount of the discount to the user's price profile.

Exit pop ups

They show up too late, just before the user leaves the store and is lost. They cannot match the amount of the discount to the user's price profile.

Newsletters

Users do not want to use newsletters because they want to get a discount right there and now while shopping. That is why they do not want to give out their e-mail and receive future offers in their inbox.