They did the same thing with Instagram, I think Twitter are doing this because these competing websites are generating a lot of new users for those websites whi

They did the same thing with Instagram, I think Twitter are doing this because these competing websites are generating a lot of new users for those websites while leaving Twitter in the dark on growth, revenue, etc. Twitter sees this as significant competition, although I don't really see how blocking these "competitors" from using the Twitter API helps Twitter?