I am sure we've discussed this before, but I am kind of stuck.
I have a large-ish team with 1 PDRA, 2 RAs and ~6 PhD students at various stages of completion. My students have historically all performed very well (prizes, papers, opportunities) - I select them as carefully as I can, and nurture them to their full potential. All are co-supervised as per uni rule, although the 2nd supervisors are mostly piggy-backing for papers, to my great annoyance and that of students. This is another matter altogether. We do PhD expectations as per Vitae guidelines early in the PhD, so have some foundations for our interactions.
Out of the 6 students, I have one who is bright, but also terribly demanding. He writes and writes and writes, and is avid on feedback, regardless of who else is submitting at the same time, whether a team member is in distress, or whether I am sick (as currently am). He also sadly subscribes to the school of thought of a certain Australian #ECR guru on twitter who advocates for "better supervisory practice" and fast feedback. I just feel like a provider to this person, who fails to acknowledge that I put a disproportionate amount of effort in his supervision.
I have tried delegating tasks to him to get him to grasp supervisory/academic challenges, and have provided him with opportunities to teach/supervise undergrads, to disastrous consequences (students complained about how they were treated as slaves on numerous, separate occasions). I have tried feedbacking light and prompt, but this just increases my workload as the draft just return faster.
I get that it is my duty to support this guy (who also has qualities) through the PhD finishing line, but it is taking its toll, and I am not sure if I have another 12 months of this left in me...