I am a developer who works on teams that use agile processes. I happen to believe they work better, based on my subjective experiences with other approaches, bu

I am a developer who works on teams that use agile processes. I happen to believe they work better, based on my subjective experiences with other approaches, but I don't really have the kind of numbers one really needs to back up each individual practice, which is something I struggle with. I don't struggle much, though. The most important aspect of my definition of agile is that it speeds up the feedback loop, which allows the person signing the checks to gather whatever kinds of metrics they need to on a week to week basis. Essentially, weekly iterations make quantitative analysis of the software development process possible. Every other practice teams do or don't adopt falls out from this newfound ability to gather and disseminate metrics which are, in principle, of much higher quality. Do write tests, or don't [ed. note: do]; but either way, track weekly, and let that guide your process.