My mom taught me to teach babies to use stairs as soon as they were mobile. Before my husband and I had stairs of our own, my mom would take our first child, and then our second, and lovingly and slowly show them how to go down (feet first) and up the stairs at my parents house. My mom did not like gates. When our third child became mobile, we were living in our current house with stairs. Ignoring my mom's advice and her example, we immediately got a gate. The gate was returned to the store the same day it was put up. My active 2 year old, wanting to go downstairs, scaled the gate. My motherly intuition told me that having a 2 and 3 year old climbing over a gate at the top of the stairs was more dangerous than teaching a baby to use the stairs.
I followed my mom's example and taught my little one to go up and down the stairs. My fourth and fifth children have been taught to use the stairs in the same way. We have only had one minor tumble halfway down the stairs, when I was still learning the importance of vigilance with my third child. Surprisingly once my children have learned how to use the stairs, they stay away from them unless they need to get somewhere. I do not know if the attraction to the stairs disappears because they are not forbidden to use them or because the stair climbing feat has been conquered.