Lines on a sailing boat slowly become hard and full of salt.
When new they seem soft and flexible but slowly they become hard and inflexible, but even more importantly they start to squeak badly and also slip occasionally in the clutches.
The answer is to get the salt out of the lines and soften them again. They will swell, shorten and soften as you do so, and be back to being as close to new as they are capable of until you actually do need to replace them.
Soak in a fresh water concoction with fabric softener to help them along. Overnight is usually enough to get flexibility back into the lines. If you used fabric softener, don’t bother with rinsing that out. just leave it in.