For every interviewer there are the ones who got away.

The interviewees who never said yes. My own list ranges from Bjork (I still live in hope), Bowie (less so, to be honest), and Neil MacGregor.

I've been wanting to speak to the soon-to-depart director of the British Museum ever since former National Galleries of Scotland director Sir Timothy Clifford once mentioned that MacGregor had been on the barricades in Paris during les evenements back in 1968. MacGregor's journey from his Glasgow childhood to one of the top jobs in British culture - a job that he enhanced - would make for a fascinating interview.

As it is, he will leave the British Museum in remarkably fine fettle, attracting almost seven million visitors last year and still basking in such exhibitions as A History of the World in 100 Objects which, via radio and publishing, reached out beyond the museum's London footprint.

It is worth comparing the plaudits that have greeted the announcement that he is to step down with the more muted farewell allowed Tate Britain's director Penelope Curtis, another director raised in Glasgow, the week before.

Curtis is departing to become head of the Museu Calouste Gulbenkian in Lisbon after a torrid few years at the head of the Millbank institution. She oversaw a successful £45m refit of the building but was attacked - bitterly - by London art critics who felt that some of the exhibitions at Tate Britain were poor. Or worse. Trade paper Art Newspaper went so far as to suggest that some of the criticism amounted to a "vendetta" against her.

Curtis (who did give me an interview back in 2011) was always going to face a more difficult task than MacGregor, partly because he had longer in the job to make his mark (he joined in 2002), and partly because he had a much clearer vision of what the British Museum should be. Tate Britain has been struggling to find its raison d'etre since the establishment of its younger, sexier sister Tate Modern. (As an aside it's interesting to wonder what would have happen to either institution's sense of itself if the indyref vote last year had gone the other way.)

Curtis, when we spoke, was very clear-eyed about the challenges of the job. Four years on it would appear that either she or the Tate felt that she has been in situ long enough.

Why does any of this matter 400 miles north of London, you might ask? Well, over and above kudos by association, in 2004 the Burrell was able to welcome a 4000-year-old sculpture from Iraq, The Queen of the Night, on loan from the British Museum. And it's just over two years since Kelvingrove - the museum MacGregor knew best as a kid -played host to the travelling British Museum Pharoah: King of Egypt. One also wonders how much say Curtis, who is also chair of the Turner Prize jury, had in the decision to bring the latest Turner show to Glasgow's Tramway this coming autumn?

Connections do matter. A couple have now been severed. Good luck to both of them. On the upside Lisbon is very nice at this time of year, I've heard.