UPVC doors commonly fail / break due to door misalignment, old age or misuse.
One of the rarer problems I’ve come across is due to the door being full of water. In one example a customer reported their door was jammed shut if it was really cold. On first attendance it was below freezing and the door felt heavy. Later in the afternoon once it was warmer you could hear water sloshing about in the door. We drained nearly 10 litres from that door before correcting the other fault.
In another UPVC door below that had jammed shut due to corrosion of the multipoint mechanism you can see the final dregs of about 5 litres of water being drained out of the door.