1. Makes families heavy and system slow.
2. Arrayed components can't be joined each other after loaded into projects.
Once I've made a 'Joinable Stair Family' couple of years ago.(I think most people would understand why I made it)
You can download the family here
This looks work fine, but it's little bit heavy and can't have joined steps when they are increased in a project. (so I had to make steps array enough numbers in family editor.)
I made this only with one sold and one void, instead Array(except detail lines).
Then, it's much lighter and no need to be joined.
This will be useful if you want any repeatativie but limited number of array is necessary in your familes.