I'd imagine since building codes maximum stair rise has been standardized. So that, plus a limited number of common ceiling heights, results in a few standard

I'd imagine since building codes maximum stair rise has been standardized. So that, plus a limited number of common ceiling heights, results in a few standard numbers of stairs. Additionally, building to standards allows you to use interchangeable materials [e.g. 1], decreasing onsite time, which usually directly translates into profit. (Labor is expensive) It seems reasonable the same has generally been true throughout modern history. [1] https://www.homedepot.com/p/5-Step-Ground-Contact-Pressure-Treated-Pine-Stair-Stringer-279714/301040023 https://www.homedepot.com/p/5-Step-Ground-Contact-Pressure-T...