“Less is more” is repeated so often in discussions of marketing that it’s easy to ignore and dismiss as an empty cliché. But clichés often become clichés for a reason, and when you seriously consider whether less is more, you ask a fascinating question.

What exactly is meant by the cliché? If we limit it to marketing jargon, we are saying that an audience is more receptive to a simple message than a complicated one.

If, for example, I purchase an expensive billboard, I naturally want to overload it with information about my business—I want to make the most of the limited real estate I have, after all, so I want to get my website in there, my hours of operation, my phone number, address, and a list of services I provide. But this can see diminishing returns, and when I try to cram too many messages into one small space, drivers are more likely to ignore the billboard entirely. To get the most bang for my buck, it’d be better if I thought carefully and strategically about my message to make it more palatable and memorable to my audience.

But psychological research suggests that it goes even further—that when I put too much information on a billboard it not only increases the likelihood my billboard will be ignored, but will actually give the audience a negative impression of my brand, to the point that I’d have been better off not advertising at all. Why is this?