Doesn't seem to me that you can really measure productivity at all. How do you compare : (a) dev that writes tons of code and makes things over complex and not

Doesn't seem to me that you can really measure productivity at all. How do you compare : (a) dev that writes tons of code and makes things over complex and not maintainable (b) dev that writes hardly any code, procrastinates, but their code is v high quality, simple, has no problems (c) dev that cranks out a lot of code but is horrible to work with and very good teammates quit (d) dev whose code output isn't high but that's cos they do tons of useful mentoring leading to other people's output being good