When inspecting a garage door, I find it important really look at the hardware and shaking it before operating the door opener. I go all the way down the track moving it. I then move across the door (Making sure the latch is not latched) and on to the other track. Look for anything that may damage the door when you open it. Garage doors are very large objects and the last thing we want is for one to be damaged during operation. So Remember to give them a good shake before you push the button.