Every once in a while, someone will mail me a single popcorn kernel that didn't pop. I'll get out a fresh kernel, tape it to a piece of paper and mail it back to them.
It was necessary to have an even depth of corn on the top compared to the sides, so the air would not take the easiest route and not evenly dry the stored corn.
We got to know the competition very well. In the '50s popcorn made a big growth in sales. Our main push was to produce the best quality and sell in quality retail outlets.