1) Arrives later 2) Barrel staves 3) Brings up the rear 4) Dawdles 5) Delays 6) Dillydallies 7) Drags behind 8) Drops behind 9) Drum staves 10) Fails to keep pace 11) Fails to keep up 12) Falls behind 13) Gets behind 14) Hangs back 15) Hangs behind 16) Has trouble keeping up 17) Internet annoyances 1) Brings up the rear