Sealing protects concrete against moisture penetration, staining and UV fading, and on the Downs it does one more job that coastal advice tends to skip: it slows the water movement in and out of the surface that repeated winter frosts turn into scaling and edge damage. Expect the concrete to be cleaned and repaired where needed before a suitable sealer is applied, forming a barrier that holds colour definition on coloured, stamped and exposed aggregate finishes. A sealed driveway is also far easier to clean, so oil marks, efflorescence and the dust that settles through a dry westerly spell come off with a hose rather than a scrub.
Recoating is generally needed every few years, and sooner on a west-facing driveway in full sun than on a shaded southern side. Sealing remains a low-cost measure compared with what it costs to repair or resurface a surface that was left unprotected.