Have you ever thought about space? Is it going to fit or not? Will it go up or down the stairs? It came in that doorway, so why won’t it go out? The secret is sometimes it just doesn’t and this is something a customer sometimes doesn’t want to hear or understand.
An example of this is an armoire that was delivered by a furniture company. It went up the stairs because they had the open space of the living room to turn the armoire in order for it to go up the stairs. When bringing it down, there was no turning space at the bottom only walls, stair rails and a ceiling overhang. What can you do? You have an angry customer who doesn’t want to understand the math and believes that magically what goes up must also go down but that logic isn’t always true.
Name-calling or telling the movers to shut up when they are trying to explain the math is not the answer but it takes all kinds. In this case, the movers didn’t leave (most would have); instead they lowered the armoire down 35 feet from the top of the house. It weighed 450lbs and fortunately the equipment was available on the truck. A great feat no less but they received no thanks from the homeowner, only criticism.
There is no magical solution if the mover tells you something won’t fit. This is their job and they do know the job and what’s best. Always work with the mover and a solution may be found. Nevertheless, some people are thankless. There are no Harry Potters in the world of moving to put 450lbs into a 5lb box.