It isn’t so much first encounters with people or situations I find unnerving; it’s first encounters with cupboards.

This is less bizarre than it sounds - being a Capricorn, neat, tidy, fastidious, I am a stickler for order and straightness. If any pencils in the pot do not lean at the correct angle; if any sheaf of papers is not stacked exactly in the precisely correct part of the desk; if The TES hasn’t been ironed before breakfast; I suffer palpitations and redness of face.

For years my cupboards and stockroom were gloriously kept and labelled. The cupboards of others I could happily turn a blind eye to - although there was always the temptation to feel smug on seeing the less-than-perfect efforts of colleagues.

But it was as a head that I first encountered the domains of others sadly less concerned than myself with the perfect order of things. “Show me a person’s stockroom or cupboard and I’ll show you the person,” became a cornerstone of my philosophy. It is a belief I have adhered to since becoming a head 16 years ago and since retiring to supply work three years ago.

The first encounter I ever had with an unsatisfactory cupboard happened just a week or so after I took over the small village school near Leeds where I had so many happy years tidying the staffroom and desk tops. I had offered to take a class while its prim, female, rather long-faced owner was given time to come to terms with the fact that something like 30 years had passed since the 1950s.

At the back of the room, near a stained and sad-looking sink, was what was called the art cupboard. It stood looking rather forlorn, weary, with faded brown doors. Confidently, I opened one of the doors to see what lay inside. I soon found out. Most of it fell out. It covered my flares and suedes in a mass of powder paint and pots of runny glue. This was followed in a sort of slow motion by the remaining heaps of old newspapers, drawing boards, tins and containers full of drawing pins, staples, and coloured pencils - all in need of sharpening. I surveyed this debacle with a mixture of calm detachment and iron-willed resolve.

The resolve was that never again would any disgracefully kept cupboard be allowed to take me by surprise. Not that this meant I issued masterful, firmly-worded edicts to staff; it just meant I opened other doors in other rooms more slowly.

Since that day my theories of personality and the individual characteristics of teachers have been based solely on my first meetings with their stockrooms.

I have encountered pristine mini-palaces you could eat your tea in and which could feature in Homes and Gardens. I have been mauled by giant rubber plants lurking unexpectedly in gloomy recesses in places looking like the aftermath of a jumble sale. I have uncovered treasure troves of wonderfully ancient history textbooks in stockrooms drowning in the clutter of someone’s lifetime collection of priceless resources. I have removed enough old newspaper to reforest Canada and Norway.

And now, more recently, as a supply teacher touring the city’s schools, I have been been privileged to have had access to the workings of people’s minds.

As a head in interviews, I never asked“describe the ideal classroom”; but always “describe the ideal stockroom”. My heart sank some years ago when allowances and points had to be awarded for inconsequential items such as curriculum, when for years I had awarded salary rises for important matters such as looking after the stock cupboard or having the best-kept shelves and window ledges.

Cupboard management to me will always be infinitely more important than senior management. And don’t you realise it’s no secret why OFSTED inspectors now insist on delving into cupboards and stockrooms. They believe as I do. “Show me the stockroom, and I’ll show you the teacher.”

David Thomas lives in Leeds