I've been seeing the notion of accounting for the loss of sales due to "reputation" come up on HN recently and I wish to dispute it.
First, most of the time when we're talking about business and we talk about costs we're clearly talking about accounting costs. This applies to startups, too. When you're talking about accounting costs, you don't get to include economic costs (e.g., opportunity cost.)
Second, isn't trying to include these extra "costs" due to lost sales the same thing that the music industry is doing? That is, claiming that they lost trillions of dollars due to file sharing from, you got it, "lost sales." [1]
I don't think there's any real way to measure these costs, so let's stop trying.
[1] http://www.p2pon.com/2011/03/25/greed-hits-climax-music-indu...