Media: The phrases that do more than they say on the tin

The Ronseal slogan was devised in 1994

David Cameron's attempt to varnish a splintered coalition by insisting it was not a marriage but "a Ronseal deal – it does what it says on the tin" has revived one of the most successful slogans in advertising. The phrase, devised in 1994, quickly achieved what ad execs dream of: a place in popular speech where words can become more famous even than the products they push.

Remember Jubbly? Perhaps not. It was an orange drink sold in pyramid cartons in the 1950s. Del Boy thought it was "lovely", later thrusting its ad slogan into the vernacular in Only Fools and Horses.

Just do it! The future's bright, the future's Orange. Because I'm worth it. I'm lovin' it. Simples! A few words can link people to products more effectively than any endorsement or big-budget ad featuring meerkats. The Ronseal phrase, which was actually "Does exactly what it says on the tin", started life as a holding line before its creators, Dave Shelton and Liz Whiston, founders of Bordello Advertising, could think of a proper one. "But then we realised a proper line would be completely wrong," Shelton wrote on the BBC website today.

"We put the scripts into research and they totally bombed. To the punters, it wasn't 'advertising' enough." Shelton convinced the client otherwise and the line stuck, later entering The Oxford Dictionary of Idioms.

A young copywriter called Frances Gerety is responsible for what is probably the best ad slogan in the world (there's another one for you, with apologies to Carlsberg). In 1947, while working close to deadline for the old US agency, NW Ayer & Son, which counted De Beers among its clients, she wrote: "A diamond is forever." We can be grateful at least that Cameron didn't borrow that phrase while reviewing the coalition.