The advertisers who believe in the selling power of jingles have never had to sell anything.

If it doesn't sell, it isn't creative.

Ninety-nine percent of advertising doesn't sell much of anything.

Never stop testing, and your advertising will never stop improving.

In the modern world of business, it is useless to be a creative, original thinker unless you can also sell what you create.

Good copy can't be written with tongue in cheek, written just for a living. You've got to believe in the product.