I don't see how the change rate matters. If one line of code produces $1M of impact, should it be considered inferior or superior to a developer who produced a

I don't see how the change rate matters. If one line of code produces $1M of impact, should it be considered inferior or superior to a developer who produced a 100k line codebase with a couple thousand commits? But measuring direct impact to the bottom line for a developer is just confusing the roles of the business development team / sales team and the devs. As a manager, do you choose who works on which feature? If so, doesn't that make your subjective choice (on who gets to make the $$$ feature) the only metric that matters?