There are people in the workplace who would use mood rings as management guides if they could get away with it. The desire for a clear, mechanical, device to take the place of hard decision making is understandable and just as wrong. Consider how these bits of management wisdom need to be qualified:
Manage by wandering around. Not if you're a micromanager who lowers morale and initiative every time you wander near the employees.
Be candid and direct. Not if you destroy crucial relationships by doing so.
Be caring. Not if the other person needs "tough love."
Be decisive. Not if the decision is significant and irreversible and you haven't done basic analysis.
Focus on results. Not if doing so will produce greater problems and create an "Anything goes" mentality.
Pick the person with the most impressive credentials. No, pick the most qualified person. They're not always the same.
Seek to achieve the most. Only if "the most" means the highest priorities.
Devote most of your time to your "vision." No, most of your time should go to establishing systems and watching out for the details that can ambush progress.