The list of $5$Ss$,$ although it looks like a housekeeping directive, supports lean production by:

identifying non$-$value items and removing them, in the "sort$/$segregate$"$ category.

reducing inventory, in the "standardize" category.

eliminating wasted motion through ergonomic studies, in the "support" category.

increasing variability through standardized procedures, in the "standardize" category.

building good safety practices, in the "shine$/$sweep$"$ category.