A manager should never write any code that is part of the critical path of the deliverable.
Every single time without fail that I have had a manager who still tries to be an active contributor, one of two things happen.
Either they never keep their commitments as a coder because they are spending too much time on their management duties including meetings, manhole up, and career development for their reports or they are horrible managers who don’t or can’t do what I need from them as a manager - get me the resources I need to do my job, play politics and manage up and especially fight for raises.
Every single time without fail that I have had a manager who still tries to be an active contributor, one of two things happen.
Either they never keep their commitments as a coder because they are spending too much time on their management duties including meetings, manhole up, and career development for their reports or they are horrible managers who don’t or can’t do what I need from them as a manager - get me the resources I need to do my job, play politics and manage up and especially fight for raises.