IMO choosing an HM requires considerable thought. Parents and prospective pupils need to realise that they are not looking for a new best friend or an entertaining dinner companion but someone who when needed will step up to the plate and hopefully do what you as a parent would do in a variety of situation good and bad.
I’ve met many over the years the most effective have definite ideas about how they want things done, they set the general tone ethos and expectations, they are usually figures of authority but still managing to be obviously very compassionate committed and caring about the pupils in their care (not easy). The relationship between the pupils and teachers is significantly more informal than you would ever find in a day school and also the relationship between parents and HMs (who are often very demanding and have unrealistic expectations ) is more informal they have to listen support read endless emails know when to stand firm, when to turn a blind eye (to activities pupils shouldn’t really be doing but that are harmless) when to break the rules be it collectively or for individual pupil, They need to be good judges of personality the shy, the confident the arrogant the lone wolves those who need help making decisions those who don’t, they need pushy pate to laid back parents, deal with complex families not all who are happy frequently acrimonious divorce parents behaving badly etc and accommodate 60+ personalities where often physical space and privacy is at a premium. On top of this they work 24/7 33ish weeks of the year so they need massive physical and emotional stamina.
We DS2 HM having met 3 1 wasn’t for us one we liked very much but as I said above that not really what it’s all about, his HM I felt was totally dedicated to the boys but was also very much in charge. We also felt that if my DS was really struggling he would be there for him although of course you hope you’ll never have to find out. But during his time at school my DS experienced a significant traumatic event, (no fault of the school) his HM did what we hoped and more he supported and cared for my DS I was frankly stunned by his genuine concern he was there for him and the practical support and help he offered nothing was too much troubler. On leaving I asked my DS about him he replied “he’s not perfect at times I find him irritating but I know that he really cares about us and is there for us.” I knew them we’d made the right choice I don’t think a parent of a child who’s boarding could ask for more.