“How do you get subordinates to take pride in their profession when a large part of their job is monotonous and unfulfilling?”
A lot of jobs are monotonous and unfulfilling, and in some cases, you can’t change that. What you can do is figure out why your subordinates are doing that job and what they want to achieve. If their goal is temporary and they really want to move to another job, let them know that if they dedicate themselves to doing great work for an agreed upon length of time, you’ll write them an incredible letter of recommendation and help them get that other job. If their goal is to move up inside the company and get away from the monotony of their current position into a leadership role, let them know the best way to do that is to do great work, take pride in what they do, and outperform their peers. Then you can recommend them for a promotion and get them what they want. And if it’s simply a short-term deal to pay the bills, or save for a trip, teach them that the discipline they learn when they do good work in an unfulfilling job will serve them well as they move on to bigger and better things.