A tool which told you there was an absolute change of 5%, but didnt tell you where that change was, would not be all that useful. I'm sympathetic to the "all-o

A tool which told you there was an absolute change of 5%, but didnt tell you where that change was, would not be all that useful. I'm sympathetic to the "all-or-none" broken windows philosophy that many developers use, but I disagree with it. If you need to get to 100% of some metric in order to get some visibility on its changes, you're just not going to get that metric. At Circle, we make hosted CI, and I frequently talk to customers who use jenkins or something, and whose tests are broken. Inevitably, they broke the tests one day, their priorities dictated that they couldn't fix it right away, so they left their test suite red. Because it was red, they didn't notice the suite getting more and more broken over time. If their test suite hadn't been binary, they would have learned immediately when they broke more tests, and they would have been in a much better place. TL;DR I blame the tools.