I'm in the mood for some really top red. I thought I might go and buy myself a nice bottle of Classed Growth Bordeaux. Or should I say Classified Growth? What's the difference? Anyway, the best bottles will be Classed or Classified. Won't they? Well, they might. But some wines might not want to be classified. And these might just be the best of the lot.

OK. What is a 'Growth'? The French word 'Cru', which the English translate as 'Growth', is the past tense of the verb 'croitre' – to grow. This has a genuine horticultural feel – growing things, a harvest, a particular harvest from a particular place. Yes. That makes sense. I'll just choose a good 'Cru Classe'.

So, a Classified Growth Bordeaux will come from grapes grown on a particularly suitable parcel of land, will it? Hmmm. It may do. But unfortunately, in some parts of Bordeaux like the Medoc, it's not necessarily a plot of land which is classified. It's a whole property which can add bits of land to its estate if it wants which are completely unrelated to the original piece of vineyard land. And yet grapes from this land will then automatically be available for inclusion in the 'classified' wine. They weren't classified before, but suddenly they are? Well, yes, sort of.

Really?? The classification isn't just about the quality of the land? Actually, often it is. In some parts of Bordeaux once the piece of land is classified – that's it. But sometimes, as in Saint Emilion, although the classification does indeed apply only to specific plots of land, and only a part of the property or Chateau or total vineyard may qualify to be classified – that's NOT quite it. Every 10 years or so the classification is revised. If you don't make good enough wine from your plot of land, you can lose your classification. Fine. Seems fair.

But who decides if your wine is good enough? Wine critics? Your peers? Do you know if the tasting judges holding your fate in their hands are any good? Do YOU have a say? And hang on, is it just the quality of the wine that could influence your classification? Or could it be your marketing plan and tourism facilities? It couldn't be that you might not be charging enough for your wine. Could it? Oh dear. Does it have to be so complicated? And does it really help me as a wine consumer to know what's going on?

I presume the Classifications are there to help me as a wine lover, not just to reward the owner. That depends on how you look at it. In the areas of Bordeaux which have Classifications with quality tiers – above all in Saint Emilion, and the Medoc with its Cru Bourgeois Classification system (a rung below Cru Classe) – property owners strive for a promotion to a higher level of Classification because it does immediately validate a higher price. Do they achieve this promotion by making better wine? In which case – Hurrah! Or do they get promotion by ticking a lot of boxes and spending a fair bit of money. In which case the wine might be better, but sure as hell it will be more expensive.

Yet the best wines are not necessarily inside the Classification. Four of Saint Emilion's top producers have resigned from the whole scheme. Other star wines, like Tertre Roteboeuf, Rocheyron, Quintus and L'If don't seem too bothered about applying for Classification in the first place. They don't see the need or the benefit.

In the Medoc's Classification of so-called Cru Bourgeois Estates, many good properties jostle for inclusion in one of its three tiers of quality. The 21st Century has seen several attempts to put the classification on a legal footing, with only partial success. So far, the latest attempt, in 2020, seems to be holding. But as in Saint Emilion, not all the best properties take part. And many owners get miffed if they lose their place in the revised Classification. In 2003, over 70 owners went to the courts to overturn the revised Classification. The latest Bourgeois classification is supposed to be revised every 5 years. It does set out quality parameters for the producers' wines. But it also marks properties for things like environmental standards, tourism and marketing. Shouldn't it just be the quality of the wine? In fact, the taste of the wine only accounts for 50% of the evaluation, and there are 249 different chateaux to wade through. That's nothing. There used to be 444! And do all the best wines that could qualify actually want to be included? No, they don't.

Well, the most famous classification of all is the 1855 Classification, largely focused on the red wines of the Medoc. Surely this was based on wine quality alone? In a way, it was. But that depends on how you judge quality. And in 1855 they judged quality by price. The market ruled.

The initial great wine property of Bordeaux had been Haut-Brion, just south of the city. But there was an enormous desire amongst the wealthy and powerful men of Bordeaux to emulate Haut-Brion's success, and the draining of the Medoc marshes just to the north of Bordeaux city exposed great gravel banks superbly suited to the cultivation of vines. These were rapidly planted and developed as prestige estates.

The wines of the first ones to be developed, like Margaux, Lafite and Latour, became the most popular in Bordeaux, the most famous, and the most expensive. Properties developed later, often, but not necessarily, on lesser soils, had less commercial clout, and weren't able to obtain the same prices, even if the wine was often just as good. And the brokers who traded in these Medoc wines developed a kind of classification strictly according to what prices they were prepared to pay for the different wines.

In 1855, when the organizers of the Great Exhibition in Paris asked Bordeaux to present a display of its best wines, the Bordeaux Chamber of Commerce simply took the local brokers' price system and divided it into five – strictly according to what price each property achieved. No one tasted the wines. No one wrote tasting notes. The market decided what was best – in other words 1st – and what was 2nd, 3rd, 4th, or 5th. The 1855 Classification, the most famous Classification of fine wine in the world, was organized entirely according to what price the market would pay.

Efforts have been made to change the Classification, and in 1961 the reformers very nearly succeeded. But those who were already Classified realised that many of them would be demoted and some would be excluded altogether. At the final vote on reforming the Classification, not one property owner voted in favour.

And we're back to the market. The 1st Growths still get a premium, sometimes deserved, sometimes not. But all the other levels now bow to the market – what price the market will bear. And that is surprisingly often based on how good the wine has become. Lynch Bages has outperformed its 5th Growth status since the 1950s. Its exalted price reflects this. Pontet-Canet in the last generation, and Pédesclaux in the last decade have transformed their quality, and their price has shot up. The fact that they are classified at ALL matters. What level they were classified at in 1855 matters less and less.

So, do the Bordeaux Classification systems help us? Up to a point. The simplest one is the Graves Classification which simply lists the top 14 Pessac-Leognan properties. It's not difficult to get the hang of. The 1855 system works in a way because all the best Medoc properties are probably in the Classification somewhere. The Bourgeois Classification is a good attempt at making sense of the Medoc's numerous properties excluded from 1855. Yet some of the best of these, like de Pez, Sociando Mallet, Siran or Angludet are not in 1855 but don't deign to be Bourgeois either. And Saint Emilion? Well, who knows? There are around 80 Classed Growths at the moment, there are the refuseniks, and there are hundreds of properties that can call themselves Grand Cru, but not Grand Cru Classe. Confused? Me too.

Of course, you could dismiss Classifications altogether. Pomerol makes some of the most famous red wines in the world, as well as many lesser offerings. The market sorts them out. And some of Bordeaux's best and tastiest, good value wines are from the Cotes – places like Castillon and Francs. They don't think they need a Classification. And it won't cost you too much to find out which ones you like and which ones you don't.