For the most part, though, marketing can get by perfectly well with imprecision. All that matters is knowing whether one choice is better than another. It doesn't matter how much better or how much worse. It's yes or no, on or off, launch or shelve, the current or the new. A big enough chance of success or not. Above the threshold of action or below.

More than ever, advertising agencies are acting as principals rather than agents. That means they acquire media - therefore becoming the owner, or "principal," of that media - and then resell the media to their clients. Marketers need to be educated about this so they can make informed decisions about the role of principal media for them.

I can hear you gasping, but bear with me. Unless consumers want something, it doesn't matter whether they need it or not. They won't buy it. Wants, not needs, motivate purchasing.

That's what a London-based anti-ad-fraud advocacy group wants you to understand, and it begins with knowing who your customers are.

"Alex's book will be the 'Ogilvy on Advertising' for the digital age," touts the publisher of Meta CMO Alex Schultz's "Click Here."