How long should headteacher stay at school?

There is a National shortage of head teachers. Unsurprisingly no one wants that level of responsibility for the low pay. I know lots of situations where 2 schools share and executive head because they are doing the LEA a favour.

Bloody hell. Who’d be a teacher?

Gosh I'm surprised you are annoyed by a lack of loyalty! Just like in every other professional teachers at all levels are free to seek promotion and better opportunities for themselves. If the school she is going to is bigger and more prestigious then she will likely be getting a higher salary - why shouldn't she want that for herself?
I've been teaching for quite a long time now - the head at the first school I worked at was there for 16 years until he retired. He was an excellent head and the school did thrive under him. My most recent school a head left after two years because he wanted to take an opportunity abroad before he retired - I never questioned his loyalty although we were of course disappointed to lose him.
I have a friend who is a headteacher - he moved around a lot in order to become the head of a large, very popular secondary - he did one 2 year headship and one 3 year headship on his way. He gets paid more and runs a highly successful school now, and he had to move around to get there.

Part of normal professional life. Not many people stay at the same company for decades these days, whatever the profession. It’s normal to move companies, and it’s no different for headteachers

Why shouldn't she move? High profile job so good career move, and she may have other reasons for wanting to move like any other woman (family etc).
As a teacher I tend to find the Heads that hang around a long time have either reached the peak/end of their career at a certain point in life and are ready to settle and/or are too old to move again, or are too mediocre for any other school to want them. Rarely happens with the women who make it to Head in these prestigious schools because a woman would never get that far if she were mediocre!

When my older DB started secondary school the head had been there since my Mum was a pupil 22 years earlier.
He retired that same year and his replacement was there for 16 years.

Heads do seem to stay a lot less than when I was younger but I think a big part of that is because the job description has completely changed and heads now are expected to do so much more so it’s probably not worth the stress.
I’ve also seen a lot of schools bringing in new heads to turn the school around so I don’t know if it means the former heads are encouraged to leave.

Turn it on it’s head. If this was YOUR job and your career, would you stay in your current role just to be loyal to your colleagues or customers?

Personally I’ve left jobs despite loyalty to colleagues/clients, but I’ve also considered the effect on my CV of moving too quickly. In my sector those who make speedy moves can attract a reputation of lacking commitment. It really isn’t as simple in many sectors as taking the best opportunity you can for your career at any single moment regardless of the circumstance or knock-on effect. Heads who don’t stay long tend to have been head-hunted by recruiters for the new school, though, so that lowers the risk of being thought lacking commitment from moving on too soon, I suppose.

I can't think of a single reason why she shouldn't work wherever she chooses - her career, her life.

I've been at my current school 15 years, but I'm not the head. In the 15 years I've been there, there have been 3 heads. The first was head at this school for 25 years, and only left as he was retiring. The next head actually had no interest in being head, she was happy being deputy but applied so there was at least one "safe" option amongst the candidates. She openly said she would not stay long, and true enough, she retired after 3 years as head. Then we got our current head. He's been in post since 2011, and as far as I know he has no interest in moving on. Maybe he will move on after his youngest child leaves the school, but I think he's here for the long term.

I wouldn't blame anyone for leaving a job though, not for any reason. Getting a more prestigious job with more money is allowed, nobody has to stay where they are forever, they just have to do a good job while they're there.

Why would anyone expect a teacher to be more loyal than any other job

3 years is loads of time to make an impact

I don’t know. Our brilliant headteacher stayed for almost 20 years just for the next headteacher to find out he left such a mess bot in finances and academic stuff that the only reason why our brilliant school was not put in Special Measures was because we had already got a new headteacher, who is doing a far better job than the previous one.

Change is good.

My dcs school head has been there for at least 11 years.

Turn it on it’s head. If this was YOUR job and your career, would you stay in your current role just to be loyal to your colleagues or customers? When the new role is with a “better” organisation, a promotion and pay rise?

Heads changing rapidly is a pain in the backside, particularly if you really liked them. I much prefer our new head though versus the old one!

Three years isn’t long enough for meaningful change, and especially with more than 1 of those years being covid. So seems a shame that a head would only stay that long, but people can move on professionally whenever they want. Hopefully the governors will put a bit more thought into appointing someone with a longer term commitment to the school now they have to recruit again so soon.

Yabu. Being a teacher is a job and head of KCS is a high profile job.

Loyalty to who? What loyalty goes she owe you?she owes you nothing

OP, the link for this lady is also on the SW London boys thread. I think when you get someone with her career path she is always going to be on the move for a big job and KCS is 1 of the biggest. I remember when Sarah Fletcher left KGS after only a few years parents who had chosen the school just because of her were upset but she then went to CLS for even less time and is now at St Paul's Girls school - 1 of the top private school jobs in the U.K. Her replacement at KGS has been very successful so often it all works out ok. But yes it's different to the old days when people stayed in post for years