Success in trade is all about supply and demand. Well almost; timing is also important. Think of the products and services that seemed a sound investment a few months ago that, thanks to the pandemic, have become dead ducks through no fault of their own.

Failure can also become success. Unpopular products quickly withdrawn from the market can later find themselves among the most desirable of collectibles simply because surviving examples are so rare.

The original Palitoy Star Wars Vinyl Cape Jawa figure had a vinyl cape that was replaced by a cloth version to make it look less cheap. So rare is the vinyl cape version that in mint condition in its blister pack it can sell for around £20,000 today.

Consider, too, the Britains Exploding Trench, released in 1915. The idea was to line up six toy soldiers in this mechanism, with a child taking aim at the flag posted at one end from a toy cannon firing a matchstick. On being struck, the flag would activate the mechanism, releasing a spring that would catapult the soldiers into the air.

The story goes that all went well until it was noted that the soldiers were British not German. However, as they wore pickelhaubes, this is probably no more than a myth. The reality is that the trenches were unprepossessing to look at and made of fairly perishable wood and cardboard. Together with overuse of the mechanism, this would have meant that few survived. The result is that this rather unpromising toy is now a collector’s dream.

Sometimes it is the lesser things in life that hold more interest – or at least are the more memorable. This can be especially true of jewellery at auction. A perfect diamond may sell for millions, but apart from its perfection and its price, there may be little else to say about it, whereas an intricately designed Art Nouveau brooch costing hundreds can hold one captivated for hours.

Oscar Wilde’s letter to the impresario George Alexander regarding his plans for what was to become The Importance of Being Earnest is rather more fascinating than a diamond and expected to fetch £150,000 as this column goes to press. While it holds many interesting gems to do with characters and plot, I find it less enticing than another Wildean lot coming up for sale in the same auction: his answers to a questionnaire when he was a student.

Dating to 1877, the two-page questionnaire reveals that the poet and playwright’s ready wit was already close to fully formed. He deemed happiness “absolute power over men’s minds, even if accompanied by chronic toothache”, while misery was “living a poor and respectable life in an obscure village”.

Wilde’s favourite occupation was “reading my own sonnets”, while is dream was “getting my hair cut” and his distinguishing characteristic “inordinate self-esteem”.

He believed the essential quality of a wife to be “devotion to her husband” and aimed for a life of “fame or even notoriety”, a realised ambition that he would later come to regret.

Much of the talk recently among auctioneers and dealers has been about online activity replacing traditional methods of selling. The discussion brings to mind how, over the past 20 years or so, the email has replaced the letter. It’s quick, convenient and effective for business, but it also means that the only correspondence that hits the doormat these days are bills (those not arriving electronically, anyway), flyers for pizza restaurants and promotional leaflets for everything from fun days out to funerals.

I pity the young who have never experienced the thrill of a hand-written envelope with their name on it popping through the letterbox. It also means that we are quickly losing that window on the soul that has helped us understand the thoughts and feelings of the notable and notorious over the years.

Two letters coming to auction in the past week or so remind us of this. The first is a poignant note from 1991 addressed by Princess Diana to a friend, in which she muses on what the next ten years will bring – a haunting thought as she was only to live for another six years.

The other is really exceptional, a thankyou letter from the newly crowned King George VI to his speech therapist, Lionel Logue (remember the film!) in which he expresses his undying debt to Logue for helping him get through the Coronation. Accompanied by the gift of a cigarette case, it sold for £76,000.

Emails may be convenient, but they aren’t everything.

Art as an asset class has been much in the news in the past week with the revelation that British Airways – beleaguered as it retires its 747 fleet in the wake of the pandemic – is to sell off work from its art collection.

Firstly, who knew that British Airways even had an art collection? Possibly the most famous public commercial investment in art in this country has been the British Rail Pension Fund, which spent generously on art, parting with £40 million (around 3 per cent of its holdings then) between 1974 and the 1990s for around 2400 museum quality works in what was a ground-breaking experiment at the time.

The investment was treated as a hedge against inflation, with the British Rail Pension Fund rivalling the Getty in reputation as a power investor in art.

Thanks to the experiment proving largely successful, many other businesses followed suit, with art becoming seen as a relatively less risky asset class once bonds and gilts took a serious knock in the crash of 2008.

Now BA is looking to offload a wealth of Young Brit art by names like Damien Hirst, Tracey Emin and Anish Kapoor as it looks to build cash reserves. Not only is this a bold move and one that could have repercussions for BA if the sale does not go well, it could also prove a landmark in the long-term fortunes of the leading Young Brits.

With things in the market fast developing, it will be interesting to see whether BA chooses to expose the works in the harsh light of an open auction or look to go the private sale route. Either way, the leading auction houses will be looking to get in on the action, but they will be up against serious competition from increasingly savvy and powerful contemporary art dealers who have already snaffled some tasty prizes from under their noses.

Watch this space.