Outdoor Transparent Sealer question …how to…….

Submitted to General Questions

Please might I ask about outdoor transparent sealers regarding future maintenance.

Our outdoor sunny exposure does a horrible number on our solid stain sealed PT deck surface. It needs nearly yearly touch up today pressure washing loosened weathered split areas and blew away paint chips.

Anyways that brings my question about transparent sealers in my situation.
Both spray 2x ( gnome) and spar Varathane (on the ski tables.)
How do you care for the outdoor sealers to prevent possible deterioration splitting or chipping that could damage the painted surface beneath?

So far I don’t see any issues but dont know what to anticipate or expect.
I feel indicators might clue in for painted items needing attention more obviously than the transparent clear coated projects.

Should it be recoated on a demand or timed yearly schedule for best practice care?
How many coats can one apply….I know cornhole boards have more than a handful.

Thanks for your time and trouble to read this!

Edit update
I live in central Virginia which has a four season climate exposure.
I do try to move and store my ski tables underneath the deck during the winter.