If you have been away from diving for a year or more, small things can feel louder than they should: weighting, mask clearing, buoyancy, entry routine, or remembering signals. A refresher puts those pieces back in your hands before the reef asks for your attention.
It also helps the guide understand how you dive. That means better pacing, better site choice, and fewer surprises once you are underwater. Most certified divers enjoy the rest of the day more after a calm reset.