The demonstration.

I found an old recording of a machine trying to put a cup on a table. It missed the edge. A technician picked up the cup, moved the tray closer to the table and let it try again.

On the second attempt it worked.

Later in the recording, the same arm held a drink for a man whose hands shook. He took his time. Nobody reached in to finish it for him.

The caption promised fewer people would need help with ordinary things. For the length of that shot, it appeared to be true.

At the end there was an address for parts. I found the manual under a different company's name. The instructions were the same.

I went back to the first attempt. The technician checked the distance between the tray and the table before he touched the machine.