By learning from David Ogilvy's blindspot.
Over Christmas, I made my way through one of the legends. A book regarded by many as the marketer's bible - written by a man whose finesse saw him crowned The Father of Advertising.
But I'm not here to spend a second telling you about marketing secrets from Ogilvy on Advertising.
Something in that book stopped me in my tracks... and I want to tell you about one of David Ogilvy's mistakes.
Can I pass you the butter?
Because the research is confirmed: margarine is poison.
It's crazy then, that marketers spent decades spreading our parents' screens and papers with claims it would save us from the diseases it causes.
Mr Ogilvy was one of these marketers.
But he wasn't a villain.
As far as he knew, margarine really was a bandaid for bad lifestyle choices.
That's because he wasn't a scientist, and relied on flawed research about good and bad fats (for a deeper dive, check out Good Calories, Bad Calories by Gary Taubes).
Ogilvy's dilemma was that he was a marketing assassin without his own knowledge of health-science.
It resulted in advertising that hurt the health of generations... and provides us with a serious lesson.
When you're ultra-specialised in a single craft, you're blind.
There's a wonderful Indian parable called The Blind Men and the Elephant.
An elephant is placed in front of a group of blind men. Each man uses his sense of touch to describe what's in front of him... and completely fails to understand the animal.
By only feeling a small portion, like the trunk, a leg or tail, none of the men can grasp the elephant's full size and shape.
Whether we're photographers, copywriters or [insert job title here], our domains are small parts of the business elephant. It makes sense then, that business owners are terrified of hiring someone who lacks an understanding of the bigger picture.
Here's what it looks like in practice.
A freelance photographer is commissioned to provide a photo for a magazine advertisement of a waterproof backpack.
Unless he's researched the recipe for a successful advertisement, it is very likely he will misinterpret the best image for this project.
In an advertisement like this, the photo has one job: arouse enough curiosity for a reader to look at the ad's headline.
So, rather than another handsome hiker smiling in front of an exotic landscape, a better shot would show the backpack half-submerged in a puddle of filthy water.
Any photographer can learn that by picking up a copy of Scientific Advertising.
For us to avoid the same slip, there's a brilliant framework we can apply to our ourselves.
A T-shaped person is highly specialised in one skill, with a deep understanding of two complementary others.
As soon as I read the concept, I realized I'd seen it in action.
During my four years of B2B sales, I watched sales guys shake their heads at material provided by marketers who'd never made a cold-call. But I also saw entire teams show deep respect for engineers who'd done their homework on delivering sales presentations.
Getting to know one of these engineers in the Netherlands, I saw how he did it. He loaded his evenings with learning: coding, photography and socializing with sales guys.
So it's a simple answer - alongside our core skill, we should nurture multiple others that complement it.
Before you go nuts putting together a study plan though, I suggest putting your ideas through a filter.
Match becoming T-Shaped with your interests.
Charlie Hoehn is an entrepreneur I look up to. While you might not know his name, you will know those he's done wonderful work for - Tim Ferriss, Tucker Max and Ramit Sethi. In a blog post, he spilled the beans on what makes his skillset so strong:
He studied the skills he was naturally curious about... which transformed learning from a chore into a pleasure.
It's also obvious how these skills will lend themselves to writing: nearly every ad or article involves a photo, video or working with a CMS.
So I'm convinced. A killer professional is neither a one-trick pony, nor a Swiss Army Knife.
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