Although fun to say "the left hand doesn't know what the right hand is doing", I think it's unlikely that the designer for Messenger didn't know that Facebook h

Although fun to say "the left hand doesn't know what the right hand is doing", I think it's unlikely that the designer for Messenger didn't know that Facebook had emojis. In fact, the Facebook and WhatsApp scissors look similar enough in style that I wouldn't be surprised if they were drawn by the same person. I think the real answer is that they are 3 products with 3 different target users, and Facebook really wants to keep them separated in the minds of users (to keep bad karma from one brand tainting another). So, "brand differentiation".