At least in larger construction, it's the pathway to the secondary stair that takes up an exorbitant amount of space, hamstrings the layout. Also, code complian

At least in larger construction, it's the pathway to the secondary stair that takes up an exorbitant amount of space, hamstrings the layout. Also, code compliant fire egress stairwells are surprisingly expensive to build, costs more than the unit cost of a living space.