Failing Block Wall , expansive soils, lack of water drainage at footing , sub grade external force

This is why you do NOT use block walls in any hillside excavated build
The force of the hill , earth and expansive soils from water is far too much stress exerted laterally for a block wall construction to maintain any structural integrity....Poured walls 10" with rebar would have been ideal.
This was a multi family structure I inspected for one of my investors from out of state ....NOT Good by any means ...plenty of walls were leaking water in and inward thrust was noted at most walls ...no ideal way to excavate to repair ..water management was poor at perimeter to add to the damage.