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Feedback Loops

I've been following the #isTDDDead debate, and I've heard feedback loops brought up often. Part of the benefit of TDD is that you get quick feedback on your designs as you go, and you know immediately if you've violated any previous assumptions.

Feedback loops are also core of The Lean Startup by Eric Ries, in particular the Build, Measure, Learn feedback loop.

Feedback loops are just limited to software development. For example, do you ever think about how much you need to turn the steering wheel? There is no way to teach someone this ability - they need the feedback of the cars movement to know for sure.

I don't remember hearing much about feedback loops during my undergrad years (1995-2000). It was around that time that Kent Beck et. al. were publishing JUnit, TDD, and XP. It wasn't until years later that I heard about these topics. Even then, I don't recall hearing about feedback loops as much as I do today.

For me, one the main benefits of Agile methodologies (e.g. XP, TDD, etc.) over traditional Waterfall methods is that you get much quicker feedback on your work. Feedback lies at the heart of being agile - you need quick feedback to fine tune the process.

I find that TDD gives me near constant feedback, that I would normally not get. If you don't practice TDD or you don't have an automated test suite that you run frequently, you have to wait much longer to discover bugs in your products, or that your product doesn't solve the customers real problems.


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