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6 Principles of Conversion Optimisation from 1923

Updated: Apr 6

Conversion Optimisation - ‘The practice of increasing the percentage of users who perform a desired action on a website through data driven decision making. ‘

In 1923 Claude C Hopkins wrote about measuring returns on advertising, and calling out those who don’t do this as old fashioned, he wrote an entire book on the matter.

As I learned about digital marketing in the last 10 years, I always believed that conversion optimization was something that was firmly a part of the internet age, something that couldn’t have existed before at least the first decade of the 21st century. And yet here is a book from one hundred years ago, giving some of the clearest advice around.

Hopkins talks about principles of measuring returns on adverts with statistical precision. They didn’t have it as easy as platforms like Facebook have made it, but through cut out paper coupons and a few other techniques he was able to have information about returns (ROI) on adverts posted - accurate to the cent.

Here are 6 principles of conversion optimization from 1923.

1. Say only what needs said

Write briefly but that doesn’t mean don’t write much - sometimes you need to say a lot.

But you always only need to say the things you need to say and not more.

If that is twenty words or twenty thousand words, every word should be essential.

2. Marketing is sales

The relationship between sales and marketing is something that people still like to discuss, define and redefine. Hopkins makes it simple.

A salesman talks to one person; an advert speaks to many people yet serves the same purpose.

A word wrong in marketing may cost hundreds of thousands in potential revenue lost, while a salesman making the same mistake in his one to one pitch would cost a fraction of that. Thus getting every word right in advertising is essential to meeting the potential for success that a product or service could see in business.

3. Measure returns

Run an advert and look at what returns it brings. Record that in as much detail as you can, don’t ignore it. He is telling us that A/B testing worked long before it existed.

Change your messaging until you create the perfect advert. Hopkins knew business people who wouldn’t change one word of their adverts even if you paid them ten thousand dollars.

The numbers are the only sure source of the answers about what works.

4. Marketing that isn’t sales happens and it’s ok, but also it’s vanity

Hopkins and his team realised that they could learn by far the most about how an advert performs from adverts designed to sell by mail order. It was the toughest form of advertising but gave the starkest information to him.

Mail order adverts get right to the point. It must if it is to have profitable returns. And while he accepted that other kinds of adverts would use space differently he encouraged the idea that one should be aware that there is a monetary cost to the vanity of such an advert.

5. People are the same as they were in the times of the Romans

The zeitgeist changes in waves and at times one advertising concept will appeal to the majority more than another, but don’t think that the people you are talking to today are so wildly different from the people of centuries ago.

For the most part the principles of human psychology have not changed over the past few millennia. Hopkins said that being good in advertising must involve competency and knowledge of psychology.

6. Headlines are make or break

Only begin when you know who you want to speak to, then write your headline for them, write it for one of them. Consider it carefully, for all the kinds of adverts with headlines, it will determine your returns.

Don’t scrimp on getting your headline right. People will never see the rest of the advert if the headline doesn’t appeal to them, so it’s worth spending hours getting a headline just right. An image may work as a draw - but it will be effective only if backed by the right headline.

Details and the Future

In 1923, Hopkins knew that more information about the products he was selling could help him sell better. If he could find the right point to highlight.

At that time, scientific articles had recently come into existence and he would pour over them to find a little known fact that could radically change the way people saw a product. It worked well.

He recognised that information would become more and more easily available, making the work that a smart advertising person would do increasingly effective.

He may never have imagined just how much information we would have available to us today - carrying in our pockets computers more powerful than those that would send a man to the moon forty years after he published his book. Yet he already understood that tracking results on adverts was effective and doable.

If Hopkins could make advertising a science long before the internet, we, in the digital era, can make the principles he penned all the more effective.

Principles are from : Claude C Hopkins, Scientific Advertising, 1923.

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