Prefer LINE_EXISTS to READ TABLE or LOOP AT

IF line_exists( my_table[ key = 'A' ] ).

" anti-pattern
READ TABLE my_table TRANSPORTING NO FIELDS WITH KEY key = 'A'.
IF sy-subrc = 0.

" anti-pattern
LOOP AT my_table REFERENCE INTO DATA(line) WHERE key = 'A'.
  line_exists = abap_true.
  EXIT.
ENDLOOP.