We design into most homes, here in Wichita,  a basement.   And local codes require that if you have a basement,  you must have an emergency escape.  Basically,  these escapes come down to one of three options:  window wells,  view-outs,  and walk-outs.  And,  any house can be constructed having any of these three escape options.  Walk-out pits, (often call walk-out, walk-up)  are a cross between the view-outs and walk-outs.   People have liked the ability to not just to be able to  view out  the basement,  but to also walk out to the backyard swimming pool,  for example.  These pits offer a home owner the advantage of a walk-out with out setting the whole basement (and house) up 4′ of elevation.  Developer sometimes restrict this 4′ rise in elevation,  because a house set at a higher elevation can throw extra rain water onto a neighbors lot,  perhaps causing undo flooding.  So pits are used as an alternative so that homes sit low and home owner can still exit the basement.  But be warned.  Pits need a drain.  And pits tend to collect debris.   Clogged drains cause the pit to flood when Wichita has one of it’s 4″ rains that can happen unexpectedly.  I encourage either a view-out or a walk-out,  but not a walk-out pit.  It’s just another maintenance requirement I choose not to have.