Well, one correct response is absolutely to figure out if the end justifies the means. Proper measurement often isn't easy or casual, between staging a reasonab

Well, one correct response is absolutely to figure out if the end justifies the means. Proper measurement often isn't easy or casual, between staging a reasonably clean test and figuring out the actual significance of the results. If you naively insist on measuring a large amount of things, especially different things, chances are pretty good you're doing it slapdash and relying more on tea leaves than science when you interpret the results. Plus you run the risk of downplaying anything that can't be given a number. I took the "don't measure all the things" lead-in more as pick your battles. If you actually have spare bandwidth to measure all the things in a valid manner, great, but some things can't be easily quantified and maybe the bandwidth is better spent qualifying them instead.