In honor of Flag Day here in the United States, I hope you're up for another connect wall! The set of sixteen words below can be partitioned into groups of four words that have something in common. And of course the commonalities have something in common, which is related to the title of the puzzle. I wish you luck!
BALL, BLUE, BRIG, CONNECT, DOC, ERR, FAB, FINAL, ORDER, PAR, REM, RIB, RUN, SLOTH, SPARE, TRY