Let me tell you about two things that have happened to me in the past 24 hours, writes Lucy Kellaway. The first concerns a shabby pair of brown suede ankle boots. The second, a glossy lipstick called Nude Lips.

The ankle boots experience has made such a deep impression on me that I have already told it at length to eight people. Far from tiring of the tale, I feel an urge to tell it again and to try to understand why it is so powerful.

On Saturday I took the boots to the shoe mender at the end of our road. The shop is noisy with its key-grinding machines and has a counter on which other people's old shoes are piled: magenta patent stilettos on top of battered brogues. An oldish man in a dirty apron looked at my boots with a cursory interest.They had been made by the fashionable shoemaker, Emma Hope, but in spite of their prodigious price, had proved so ill-suited to wearing that after a couple of months they were in tatters. Can you save them, I asked. He said he could.

Twice I returned to pick them up but he hadn't done them. He was apologetic and called me "my dear", which I always like.

On the third visit the shoes were ready. The new leather soles were perfect. The ragged suede on the heels was smoothed. The uppers were tidied up and waterproofed.

The price was £23.90. I told him I was delighted, and that he had done a wonderful job. He looked gruff in the way that shy men do when they are pleased and instructed his employee not to charge me for the black shoe polish I was buying.

The whole experience gave me a strange jolt of delight. Indeed, I was so buoyed up that when I got home I rounded up all the black shoes in the house, most of which have never seen shoe polish in their downtrodden lives, and gave them all a scrub.

This morning, wearing the repaired boots, I stopped off on my way to work at Space NK, an "apothecary" that sells expensive make-up. A courteous shop assistant asked if she could help.

I said I wanted a lipstick that makes it look as if you aren't wearing any and she stood there patiently as I daubed "Baby Lips", "Sexy Lips" and "Nude Lips" on the back on my hand. At the till she wrapped the chosen lipstick elegantly and gave me not just one free gift but four, including a sachet of "Laughter Body Balm" and "Nude Age Defence Moisturiser".

As I cycled away I felt nothing. No warm glow. What was the difference between these two consumer experiences, I wondered. Why was I delighted by the heel bar, forgiving of the slow service, thrilled with the new soles and touched by the gift of shoe polish, and am now recommending the shop (The Master Cobbler, London N5) to everyone irrespective of whether they live nearby or have any shoes that need fixing?

Why was I slightly chilled by the beautiful shop and utterly uncheered by the lipstick and assorted gifts? Why did I feel such warmth towards the monosyllabic man in the dirty apron, and nothing at all to the groomed young woman?

First, because as a consumer I am weary and spoilt. A luxurious shop gives pleasure the first time, but after that diminishing returns set in.

By contrast, having something mended has become an exciting novelty, a nostalgic return to how things ought to be. When I was a child everything was mended. Kettles, watches, clothes, TVs. Knives were sharpened and sofas were reupholstered. Even socks were darned - my mother had a wooden egg to do it with.

Now shoes are really the only things we bother to fix, and the sheer satisfaction of having a favourite pair made serviceable again feels more rewarding than buying them in the first place.

The next reason for my delight was the rarity of dealing with a decent person who manages his own shop.

After a total of four visits I liked this man and felt he cared about my boots. He had a craft that he was serious about. And if he felt like giving away shoe polish, then he did.

This man had probably never heard of "empowerment". Or of "customer delight". Or "authenticity", and even less, "passion" at work. If he had, he would surely have thought them pretty rum ideas.

And yet unknowingly he was supplying all the things that service companies strive to provide in vain.

The scale of my pleasure shows how starved I am of the pleasant everyday encounters that used to be a part of shopping. A little bit of human warmth is now so rare that it touches us and makes our day when we see it.

I suspect there is something in the nature of a big chain that squeezes it out. The Space NK woman was well trained and was following all instructions to the letter. Yet simply by doing it right, she was doing it wrong: the result was chilly.

Indeed, the more companies try to talk the language of customer delight, the more dismal the result. Delight can't be made through formula, and can't be made from handing out Laughter Body Balm willy-nilly.

It is made when someone does his job with decency and professionalism and who occasionally dispenses an unforced half-smile along with a little tin of shoe polish.