The average interior corridor Residence Inn and Towneplace Suites hotel generally has one building. However, some locations have two buildings. What is the logic behind this?

If they had exterior corridors, it would make sense.

I ask because my parents and I stayed at a Residence Inn in Louisville KY in 2017, which was all interior corridors and had two buildings. Coincidentally enough, my parents stayed at an exterior corridor Residence Inn in that same town back in the early 90's...no clue if it's still a Residence Inn or it left to become a Sonesta or Hawthorn like most of them have become.