Targeting
With paid media, channels are selected on the basis of how efficiently it can reach a particular group of buyers and their respective attention elasticity.
"The most effective and efficient campaigns talk to the whole category (existing and potential customers). Broad reach (the widest sensible view of the prospect pool) is better than tight targeting." — Byron Sharp
"For frequently purchased package goods, share returns to advertising diminish fast, typically after the third exposure. After the third exposure, advertisers should focus on reach rather than frequency." — How Advertising Works
"Recruiting new customers is generally much more effective, especially over the long term (reach > frequency)" — Ehrenberg-Bass Institute for Marketing Science
"In mature, frequently purchased packaged goods markets, returns to advertising diminish fast. A small frequency, therefore (one to three reminders per purchase cycle), is sufficient for advertising an established brand." — How Advertising Works
Ads mostly affect people who are in a "deciding" minset when the ads run. — Thaler & Sunstein
"Regardless of the nature of the purchase decision, penetration is always the main driver of growth" — Effectiveness in Context
"The reality is that few brands are exclusively bought for specific consumption situations" — How Brands Grow by Byron Sharp
"The truth is, markets are less segmented than we assume. Successful brands have broad appeal. So it's crucial that planners understand the 'typical' person. Unfortunately, advertising people are far from typical." — How Not to Plan