Situation: I am pulling a brown chair with another brown chair next to it on my right.
Alternative situations: I took a seat in the chair to relax and to my right was another chair. After cleaning the desk in my 10 o'clock direction, I am dusting off the chair in front of me, while another chair in my 2 o'clock direction looks dusty, too.
Question: What allows the chair to my left move easily on the floor?