Last week I celebrated my pearl anniversary at the Financial Times. For the past 30 years I have been pitching up to work at the same place, week in, week out, interrupted only by a succession of maternity leaves – all of which are now in the distant past.

Five years ago, when I had been working at the newspaper for a mere 25 years, I wrote a column about it, concluding that such long service, though excessively unfashionable, was more a good thing than a bad one. To celebrate that anniversary the FT gave me a cheque, and I spent the money on a heavy silver bangle, which I’ve now lost.

This time I had planned to draw a veil over the whole thing. There would be no columns and no silver bracelets. There is something mildly shameful about being almost the longest-serving journalist on the newspaper. I can think of only three others who have been on the FT longer, and one of those has the excuse of being the editor.

Worse still, I recently came across a “talent manager” who revealed that, at the large company where she works, they view 10 years as the right time to start edging people out, as by then they have become stale and insufficiently thrusting.

But last Thursday I cycled into work in the early morning sun, making a journey I've made many thousands of times before, and as I passed St Paul's Cathedral I found myself feeling not only unstable, but borderline joyful. Warren Buffett, I reasoned, has done 50 years at Berkshire Hathaway. Carol Loomis did 60 at Fortune. They prove it is possible to be with the same outfit forever without becoming a gormless, unimaginative loser.

When I got to the office, on impulse I fired off an email to the entire newspaper inviting them to eat cake with me that very afternoon – and soliciting reflections on what 30 years’ service means.

Loyalty – mixed with stupidity, one colleague replied. Wrong, I thought. Loyalty has nothing to do with it. I would have happily been disloyal; it just never seemed in my best interests. And as the media organisations I might have joined have subsequently been disgraced or impoverished or both, it didn’t turn out to be so stupid either.

Narrow, suggested another. He had worked in lots of places and felt broader as a result. But is broadness a good thing per se? Surely narrow is fine if the work goes on being interesting and varied. If every day or week you have to find something comic or curious or new for an article or podcast or video, isn’t that more than enough stimulation to last a working lifetime?

A third colleague, also a long-timer, complained that staying in the same place meant getting dragged down by politics and that old grievances fester. Possibly; though I see it the other way round. Long service has cut me adrift from politics and has meant I don’t have to waste time working out who is trustworthy and who isn’t, as I know that already.

Writing this, I am starting to feel defiant. Why am I apologising and explaining? When someone has been married for 30 years, they don’t feel the need to justify themselves. Such stability is universally admired: it’s a sign you have chosen wisely, and then made it work.

We don’t approve of promiscuity in relationships, so why do we admire it in employment? I know someone who has worked at five different investment banks in eight years. Every time he has “passed Go” he has become richer, which is nice for him, but I don’t see what is admirable – let alone broad – about it.

As pearl anniversaries at work are now freakish occurrences, they ought to be valued more than ever. Once upon a time, long service implied that the person was too dull-witted to leave a dreary job; and that the employer was too benign to fire them. But now most places are relatively meritocratic; the hopeless are usually encouraged to shuffle off and be hopeless somewhere else.

Thus a 30 years’ service suggests a mutual choice to stay together. As one of my colleagues said, my anniversary proves only one thing: that I have been very lucky. I have found somewhere I like, and that likes me too.

So as everyone gathered around and ate cake last Thursday, I chatted to people, some of whom I’ve known for 20 years and some of whom I’d barely met. It then occurred to me that you don’t need to go to a new employer to get new colleagues. If you stay put, they come to you.

I asked one bright young man who has recently joined how he would feel to still be at the FT in 30 years’ time, and he gawped at me speechlessly. This was partly because his mouth was full of cheesecake, but it was also because he simply couldn’t imagine that amount of time. Which I suppose is fair enough – on that spring day in 1985 when I turned up at the FT for the first time, he wasn’t even born.

– Copyright The Financial Times Limited 2015