UK Net Guide, an independent guide to UK websites, found that nearly half of 1,000 shoppers polled on its site did not properly understand the meaning of the phrase "never knowingly undersold", which John Lewis has used to promote its price-matching policy since the 1920s.
According to research, some 21% of respondents thought that it had the exact opposite meaning than the one intended, and that the company never purposefully charged lower prices than its competitors.
Nearly one-fifth thought that it meant that John Lewis never deliberately charged more than competitors, with 57% understanding the true meaning -- that the company is committed to never consciously charging higher prices for the same goods as competitors.
While 61% of respondents correctly identified the slogan as belonging to John Lewis, 17% thought it was used by Homebase and 10% said it was from Marks & Spencer.
Paul Mead, head of sales at UK Net Guide, said that it chose to poll the public about the John Lewis strapline because it is one of the oldest still in everyday use.
"The danger of using a long-established company strapline is that it can become so familiar that people actually don't stop to think what it means any more. It just becomes part of the wallpaper," Mead said.
The survey found that nine out of 10 people polled would not use the word "undersold" in common usage.
John Lewis refused to comment on the findings.
UK Net Guide aims to help people to find the best UK websites without resorting to search engines. Each site gets a rating out of five stars, in areas such as mobile phones, cars and mortgages.
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