Decks Deck fittings should be removed every few years, to inspect the wood beneath. Put a good coat of sealing compound beneath and in the bolt holes before refitting. Sealing compound is a subject all of its own which I won't go into here. Most people have their own preferences. I consider it a good compound if it is still adhering and at least flexible enough to move with the wood after a couple of years.
Some cheap ones shrink and go hard and brittle.
Don't economise on these safety items. As with the hull, use stainless or phosphor-bronze bolts. Similarly, check chainplate, davit and tabernacle bolts and fixings. If a laid deck and you don't have any leaks, you are indeed a lucky owner. Check the underside of the deck for water stains, use a torch if needed to look in every nook and cranny.