Unique: a useful word, used frequently by brands to justify their position ’ and jumped on by lawyers eager to prove otherwise. Used so often in fact that it becomes a non-word... So many brands claim to be "unique', very few actually are.

And even when a brand finds the clear, defendable territory it needs to secure its place in the minds of customers, there's no guarantee it will stay "unique' forever. New competitors arrive, products date, disasters happen.

"Brands need to evolve to survive."

Of course a brand consultancy is going to say that. Of course. But doesn't it all sound a bit too familiar?

Where it all goes wrong

The very thing that makes you stand out can become a target for the latest young pretender. Take comparison sites for example: it's their easily replicable formula that does it ’ they have been forced into some of TV's most irritating ad wars to try to stand out, dispensing with customer goodwill in the process.

Similarly, products advance and brands need to innovate to stay cutting edge. Take the cautionary tale of Nokia. How we all trusted it like a best friend; that 3210 with a four-day battery life and a single game that happened to be the best game in the world. But now, with smart phones the new mobile companion, Nokia simply hasn't kept up.

And sometimes, brands fall into disrepute, tarnished by negative publicity. Then a rebrand is essential; often as a last ditch attempt to improve public perception. BP spent $500m restoring its brand image after the 2010 Gulf of Mexico oil spill. The environmental connotations they'd bound up in their "beyond petroleum' tagline seemed pretty meaningless when said petroleum burst forth across an area the size of Uruguay.

So you could say that the better brands evolve to stay nimble. From Burberry to the Fiat 500, EasyJet and McDonalds to Old Spice in the US, there are countless examples of brands that have responded effectively when their distinctiveness, relevance and/or reputation have been called into question.

Better yet, are the brands, like Macmillan or Tate, which evolve proactively: to ensure that they need not react to survive.

So far, so typical of a brand consultancy's view on the world.

But what if you had a brand that ’ from the very beginning ’ was so effective that it could maintain its position with very minor evolution?

Are there brands like this? And, more importantly, what do they have in common?

A study in superbrands

Take a look at some of the world's biggest players. They may not be the most cutting-edge, or even the loved, but they're successful for a reason.

Coca Cola's central idea of "unbottle happiness' has stayed consistent throughout its campaigns, in various different creative guises. As far back as the '80s, the Pepsi challenge showed that even though Pepsi wins on taste in a blind test, Coca Cola remains the best loved brand.

Ikea has always been clear in its proposition, staying true to its original offer of "affordable good design for all', even in the face of stiff High Street competition. Its in-store experience may be less than universally popular, yet we love its bright, irreverent TV ads, and buy its Malms and Billies in droves ’ because it balances commercials with end benefits.

And then there's Lego, long-time champions of imagination and creativity: a message that came though loud and clear in 2014's hugely successful Lego Movie, which struck a chord with kids and adults alike.

A truth universally aknowledged

Often the best way to endure, and to endure well, is to have something that's not unique per se ’ but rather is the best articulation of a universal truth. Something that can find mass human appeal, enter the public psyche and tap into common consciousness ’ and then be defended consistently and creatively over the years.

Just take a look at Apple. These days, its products are not neccessarily the best, most innovative on the market. Yet there must be a reason why it is so fetishised by everyone ’ from industry geeks to teenagers.

But what the teenagers don't remember is that Apple floundered in the late '80s and early '90s, shortly after firing Steve Jobs, and only found its feet again after he returned. Now it's untouchable. It hasn't just channelled Jobs' ethos, but immortalised it. His vision and world-view ’ a pursuit of perfection in everything ’ turned out to be Apple's clear defendable territory.

So, perhaps brands would all do better if they stopped focusing on the things that make them different from each other, and started thinking more creatively about what they have in common with us all.

Alice Walker is a Senior Writer at The Clearing & Rosalind Bull is a Consultant.