It's a useless metric in any project. A million line code base can have a lot of value or negative value. If you wrote that at 10 lines/hour your productivity

It's a useless metric in any project. A million line code base can have a lot of value or negative value. If you wrote that at 10 lines/hour your productivity is anything between -X$/hour and +Z$/hour. What does productivity mean in software engineering? Not # of lines of code produced.