In Africa at least, and I am sure the same is true of South America and Asia, there is often an assumption that the best teachers are British. To be taught by a true Englishman (men are still valued more than women) means that you will be taught well and taught properly. The number of schools around the world offering Cambridge qualifications and following the British National Curriculum is testimony to the faith in British education (despite the unhappiness with the system in Britain itself). I have been privileged to work with some really great teachers in my life and I do admire much about the British system of education, although I have reservations about others.
However, some of the 'international' teaching staff I have worked with in Africa, and they haven't all been British, have been questionable. Africa is still a place where one can run and hide from the world, perhaps even inventing a new self along the way. When someone tells you they have travelled to over 100 countries and worked in 12, you don't necessarily doubt them. When someone tells you they went to a good school or they worked at a good school or they were headhunted for the head's position, we think that it is admirable. We often believe what other people tell us about themselves - at least initially. The flaws in their stories are discovered later, in the way they behave, the comments they may make. Unfortunately, what happens then is that they usually move onto another place. They either disappear in the middle of the night, like the school chaplin who took photos of boys in the shower for 'artistic' reasons did at one school I was at, or the board, embarrassed and hoping to get rid of them as soon as possible, pays them a considerable amount of money to leave - which they do - and they go onto another school with a glowing reference.