Leaks can happen but are usually rare and avoidable.  Most leaks are patchable, and each Air-Dock comes with a patch kit.
Most leaks are caused by the air chambers rubbing on the dock or other structure.  When quoting, we will check to see if your docking space is wide enough to accommodate the suggested lift and protect it from rubbing.  In narrow spaces, some users attached boat fenders horizontally to the sides of the air chambers for extra protection.
Additionally, we sell individual air chambers, so should you have an issue, each one can be replaced without needing to pay to replace the whole lift.