The door stops partway up for no reason, or opens fine and then refuses the next time. Some days the keypad works and some days it does not.
The door opens about a third of the way and stops. Turning the limit screw on the head has made no difference, and the trolley seems to sit in the wrong place along the rail when the door is fully closed.
The belt looks fine from a distance, but up close the rubber has cracked across the back in dozens of places and, in one spot, you can see the steel cords showing through.
The bedroom above the garage shakes every morning at six when the chain drive fires up. Everyone in the house knows the moment someone leaves for work.
There are no sensors at the floor at all, or a previous owner has wired the pair together up beside the motor so the beam never crosses the doorway. A home inspector has just pointed it out.
The remote opens the door only when you are almost underneath it. From the end of the driveway you press five or six times and nothing happens.
The house came with a controller already screwed to the garage ceiling and a sensor on the door, but the app insists the device belongs to another account. The seller has moved provinces, the emails go unanswered, and every evening the door still reports to a stranger's phone.
After a week of lifting the door by hand you pressed the button, hoping it would catch. Instead the motor grinds, the trolley thumps against the end of the rail, and the little lever that should snap back stays stubbornly upright.