From Motability website:
“When you hand back your car, your dealer will take a photo and brief description of the car’s condition. We know that over the course of your lease your car may show signs of wear and tear including minor scratches, dents or damage caused by wheelchairs or other mobility aids. However, if your car shows no sign of serious damage, you could be eligible for the bonus. You may still be entitled even if you have made an insurance claim or have a car on a low mileage lease extension.”
Hope that helps.