Most gliders come with a sacrificial layer for protection. It is called rubber and it is on a little round thing tat you lower before landing. Checklists and mindfulness keep this thing as the number one protection against damage while landing! You could also install a steel plate but why, just use the wheel. Now the glide computers, independent micro switches and checklists are all guards against somehow forgetting to put the ship in landing configuration.

One poster wrote that radio warnings to a pilot on final is prohibited, really? If the verbal memonic check and the gear warning system were not working, I would want to know if my gear was up. I can fly and think, if I can safely lower the gear I would and have very low. If someone radioing you that your gear is up causes you to crash, the cause was not the radio transmission rather the pilot's failure to adequately aviate. If we adjust all radio transmissions for the absolutely lowest possible "skill" level, maybe we should require a higher skill level. I know accidents happen, but this is one that is avoidable with two checks before the radio transmission.