Yep, yep, and YES! Bringing a product into production is a huuuuge headache compared to a development cycle or a one-off build-up. Getting the parts and raw materials reliably is one headache, fine tuning your product production is yet another. Parts/materials suppliers come and go, the part you found that's just perfect isn't made anymore or isn't available from your supplier, materials suddenly become scarce or pricing goes through the roof, etc, etc. I learned this when I started making my Sistrums in quantities of 5 at a time. The first 2 were easy, after that I'm always having to change things to accommodate new supply realities, both in how I make them and where/how I get the materials needed. And that's just about as chickenshit of a product that you could imagine, yet the headaches are there nonetheless. My years in the Manufacturing Engineering dept. of an industrial computer company taught me well!OH I totally get it. I do IT for manufacturing. Unless you do it, almost no one gets "first run/prototyping/development" costs and issues. Everyone just sees the production runs after they swipe the card. I hobby fab in my garage when I need to but nothing on your scale or skill.
A friend designed a HELL of a nice rifle rest. He was going to start making and selling them, everyone of his acquaintance wanted one, including me. He tried valiantly, but was unable to make the jump from a one-off to production. Its too bad, as I was able to try his design at a shooting event several years ago and it was wonderful. I can only imagine the headaches @mrblaine goes through for his products!