The Law of Supply and Demand in Marketing

“The advertisers who believe in the selling power of jingles have never had to sell anything.” – David Ogilvy

Modern economics is based, in part, on the law of supply and demand. If an item is rare and people want it, they’ll pay through the nose, driving the price higher. On the other hand, a large supply of a product, coupled with dwindling demand, can cause the price to plummet.

Well, marketing too has a law of supply and demand. It goes something like this…

When a product is difficult for the consumer to find, your advertising copy can be short, to the point, and straightforward – with little or no embellishment necessary. An example is the classic ad for Hitchcock Shoes, a mail-order company that specializes in shoes for men with wide feet.

The headline of their small black-and-white space ad, unchanged for decades, reads:


The visual is a picture of a shoe against a white background.

Now, this would probably get a failing mark from most copywriting experts. But Hitchcock Shoes has been running this ad virtually unchanged for as long as I can remember. It works because of the lack of availability of shoes for large feet.

There are plenty of shoe stores. But it’s extremely difficult for a man with wide feet to find his size. So when he sees Hitchcock’s ad, the headline immediately tells him – in a direct, straightforward fashion – that they have what he needs. Since he can’t get shoes anywhere else, the ad doesn’t have to be creative… or even enumerate the benefits of the product. It merely has to call the reader’s attention to what is being offered.

For a product that is difficult to find – like EEEEE shoes – a simple ad like Hitchcock’s can work like gangbusters. On the other hand, when you have a lot of competition in your category, then your advertising must be powerful and persuasive. It must extol the benefits of the product… show how the product solves the prospect’s problem… and how owning it can make his life better.

The ad must also say these things in a fresh, compelling way. Why? Because everyone else in the same category is making similar claims – and saying them in pretty much the same way.

Consumer health information, for instance, is a highly competitive category – filled with newsletters, books, magazines, and websites.

In a promotion for the health newsletter “Bottom Line Natural Healing,” the headline focuses on weight loss. But the copywriter wisely avoids saying something like “Lose 10 pounds in 5 weeks.” Such a headline has a clear benefit, and probably worked 10 or 20 years ago. But today, the consumer has seen it so many times, it has no impact. So he has to say the same thing – “We can help you lose weight” – in a fresh and compelling way.

He does it admirably with this headline:

10-CENT TUMMY TUCK puts plastic surgeons out of work!

Okay, so where does that leave us?

Well, in addition to the law of supply and demand in marketing – which says that the greater the product availability, the stronger the advertising must be – there’s another factor that determines the degree of creativity, or lack thereof, needed in your copy: whether the product is a luxury or a necessity. Or, to put it another way, whether the customer NEEDS what you are selling vs. whether he WANTS it.

You don’t have to have clever, A-level copy to sell dialysis treatment to a patient with kidney failure, because he needs the dialysis and will die without it. On the other hand, people may want better health and a longer life – and buy nutritional supplements to gain these benefits – but few of us really NEED nutritional supplements. A heart patient may need a pacemaker, but taking folic acid is probably optional.

This is the reason why so many long-copy nutritional supplement promotions you see are such powerful marketing pieces: You need to pull out all the stops to get the consumer – who has a clear choice of whether to take your pill or not – to buy. An example is a recent promotion for Sun Chlorella, a nutritional supplement made from algae. The headline of the mailing reads:

Can these fruits, vegetables, and even bagged salad be the cause of your worst health problems? 100,000 scientific tests say YES!

You have to grab the reader by the lapels with your headline because, while the consumer wants good health, he isn’t sitting there thinking, “I need algae.” Putting the word “algae” right up front in your headline would likely get him to toss your mailing in the trash. But… if a change in the Earth’s environment suddenly meant you would die without consuming a sufficient amount of algae daily… and if Sun Chlorella was the world’s only source of algae… in that case, you could send out a postcard that simply said “Algae tablets available!” and generate more orders than you could ever hope to handle.

To sum up, two factors determine how creative – or direct – your copy needs to be:

1. Product availability
2. Need vs. want

When a product is an absolute necessity and scarce, then straightforward, clear, direct advertising messages work best.

When a product is a luxury and the category is cluttered with competing brands, you need a kick-butt marketing campaign to sell your prospect on why he should try it.

[Ed. Note: Master copywriter and best-selling author Bob Bly is the editor of ETR’s ETR’s Direct Marketing Masters Edition. a program to help you start your own successful direct-mail business. Sign up for Bob’s free monthly e-zine, The Direct Response Letter, and get more than $100 in free bonuses.

Correction: Bob Bly’s article, originally published on 8/22, referred incorrectly to an ad for extra wide shoes. The ad was for Hitchcock Shoes not Hancock Shoes.]