Anger works against the work

Think about what actually gets done on a good shift. The kitchen runs because the line covers for each other. The ward holds because a nurse flags what the next shift needs to know. The job site moves because the framer and the electrician stay out of each other's way. Work is people fitting together, and almost nothing of value gets built alone. Anger pulls the other direction. It splits the crew, it burns the favor you'd need tomorrow, it makes the next person reluctant to help you.

Seneca set the two against each other in one clean line: "Mankind is born for mutual assistance, anger for mutual ruin" (Of Anger 1.5, Stewart). Look at what each one loves, he says — assistance "loves society," anger "estrangement." The one helps even strangers; the other attacks even its dearest friends. That's the keystone of the whole week. Anger isn't just unpleasant or unprofessional. It works directly against the thing your work exists to do.

So governing your temper isn't only self-control. It's loyalty to the actual job — to the team, the patient, the customer, the build. When you hold the snapped reply, you're protecting the cooperation that the work is made of.