Ralph Waldo Emerson, in "Self Reliance," wrote that "A foolish consistency is the hobgoblin of little minds, adored by little statesmen and philosophers and divines."
We can see his point. Petty authority figures fall in love with enforcing rules to the letter. On the other hand, when you are in a supervisory position, it's generally a bad idea to make exceptions. Please have a look at Matt Reed's essay in Inside Higher Ed. He writes as an experienced dean at a community college. The piece is insightful, with implications for non-supervisors as well.
Let's say a faculty member asks a department chair for a later morning schedule, since the teacher has children and needs to get them to school each day. The chair says yes. Now the other instructors start to chatter about special treatment. Why should we be punished for not reproducing? The accusations can get far worse.
As teachers, one way to relate to supervisory dilemmas is to consider our own particular set of rules: the syllabus. We enforce it every day, with frequent requests to make exceptions. Can I take my final at a different time? Can I do extra credit?
Let's assume the request does not involve a disability or other legal protection. It's just a student in a jam, but you don't allow extra credit, as stipulated explicitly in the syllabus. However, in a moment of weakness or sympathy, you bend the rule. Then the chatter begins about playing favorites and how to game the system.
Dr. Reed makes the case for consistency, and it's a good one. But it is probably impossible to nail down every loophole in a syllabus, without looking petty and …well, foolish.
A response to students that usually works is something like, "I'd love to help you, but we need to stick to the syllabus. I can't treat you differently from the other students." They generally get that last part. This approach can be seen as cowardly or petty (The Syllabus Must Be Obeyed), but making and enforcing rules is part of the deal. Students should learn this as well.