I was waiting for a colleague of mine a few Saturdays ago, in the lobby of the local credit union – which is a bit like a local community bank. When I got there there was no-one in the queue, and I had been in earlier, when business was very slow. Five minutes later there were 6 in the queue. Just my luck I thought, and it reminded me of the old adage about waiting for a bus and then three come at once – although I suspect that has more to do with bus drivers moving in packs because they can complete their route more quickly by alternating which bus picks up the poor punters at which stop.

Queuing theory is fascinating. The whole science of it fascinates me both as an observer and a not very patient queuer. Back in the day we would all queue for a specific teller, and it was always a trick as to which line to pick. These days you see banks employing one queue which then distributes to the next available teller, and you see it also in some parts of supermarkets, airport passport controls and retail outlets. But, then again, you still see situations where you queue for your teller of choice, like in, well, other parts of supermarkets, airport passport controls and retail outlets.

I remember doing a bit of queuing theory at college when I was doing my MBA. It involves quite a bit of calculus – a subject which always sends me thinking about the unbelievably clever soul centuries ago who invented those formulas in the first place.

I mentioned this to my colleague when he turned up. As it turned out, he had an even more nerdy interest in queueing theory than I did, and we then proceeded to debate the strategies of some retailers to offer fewer servers so that the longer queues deter people from revisiting, pushing them online, though it’s highly risky.

But, the fact that you can use mathematics to account for and plan around the sheer randomness of something like people turning up somewhere and queuing is amazing to me.