I would assume that the actual making of one cap would take a minute or so and still wouldn't be ready for sale quite yet. But designing molds and getting them made and ready for actual injection (if they do injection molding) plus materials and tinkering with colors is probably the most time consuming and very expensive part. But even at a minute or so per cap, if you have to make hundreds it could take a long time. And if your mold only makes one at a time I would think popping the cap out and re-setting everything could be quite time consuming. Then you probably have to file off sprue marks and imperfections and all that stuff afterward. Then packaging and shipping each one. So yea, it's most likely a lot of work. These guys deserve applause.