I'm sure they do conduct a lot of research. However, I bet that research points toward failing batteries after 1-2 years as the major driving force in phone upgrading. If an OEM makes an easily removable battery phone, they are essentially killing their chances of future sales. The Lg g5 is a good argument to this case, but I feel it was mainly DOA because LG at the time was not conducting enough testing on their phones (Bootloop problems).