I believe he is warning against the Coffee Shop fallacy. IE, you may like coffee, but if you think running a coffee shop is a good way to enjoy/experience coffee, you are unlikely to be in business long.
It also seems like he's saying that "code" as an aesthetic principle is a very small part of your business. Your code is a means to an end (for your users), and does/should not hold much of your attention as an intrinsic ideal.