The best PMs usually emerge from support

But they burn out quick because the know the pain is there

> Product rarely uses their own product... nobody wants to eat their own dogfood

I somewhat agree with you, and think you're right at least part of the time. The main disagreements I have are (a) dogfooding is not a panacea; it can result in products that are built for the user who pays the least rather than for the wider market, and (b) too often, Product is simply not hired from the market. Product rarely works when the person coming into the role was a software engineer who got an MBA, unless the product is also used by software engineers. I can't imagine trying to lead Product for, say, Excel, without a background as an accountant or banker, who lived with the problem day-in-day-out and has strong opinions about what the solution looks like.