“The only argument as far as I'm aware for why you would want product management to be a specialist function is really it's a trade, not a qualification. And what I mean by that is it's something you get good at by doing. It's a muscle, for want of a better term. And as every private trainer has ever told me, muscles are built by reps. And so the more you do it, the better you get at it. But the flip side of that is the more you abstract your engineers and your designers from doing the same thing, their muscle gets underdeveloped.”