what this case is made of
The barriers here do not repeat: it is wired into how the customer already works, it is already on the route the customer buys through, and it makes it for less than anyone else can. One is a reason to hold rather than a reason a rival cannot displace it, and it is not forced into a kind.
Read off the kinds of reason, not written by hand. No fifth held back and no summary above them that says something the four do not.