…stairs from the garage leading directly to a basement can minimize a lot of problem issues. One of the most obvious is moving large/bulky items in and out of that lower level. Relying only on an interior staircase may present challenges, particularly if that inside staircase has angles or is “U-shaped” when moving furniture.
Additionally, direct basement access from the garage can be quite handy for home and D-I-Y projects. Your workbench and tools may be located in the garage, in the basement, or in both locations; certain projects require more room in which to spread out.
Also, if the lower level space is finished off for casual entertaining, you may prefer your teens go in and out directly through the garage, especially when it’s “band practice” at your home!