−Before storing user input, suppose we trim its edges, convert it to lowercase, and collapse repeated spaces. Nested calls such as collapse(lower(trim(s))) read in the opposite direction from their execution order, trim, lower, collapse. Adding or removing stages through configuration means rewriting that nesting for each case.
+Suppose we trim user input, convert it to lowercase, and collapse repeated spaces before storing it; with nested calls such as collapse(lower(trim(s))), the reader follows the opposite direction from the execution order, trim, lower, collapse. Adding or removing stages through configuration means rewriting that nesting for each case.
