Procter and Gamble spent $7.2 billion on advertising in the year to July 2016, according to its annual report, including worldwide TV, print, radio, internet and in-store campaigns.
It has already cut the number of marketing and media agencies it works with by 50 percent, aiming to reduce complexity and get better work.
Pritchard also implored agencies to stop talking him through PowerPoint presentations before showing him advertising ideas.
"How much time is spent polishing and re-polishing PowerPoints? Don't you just love it when you get a PowerPoint as pre-reading, only to have it re-presented to you in the meeting?
"Have we lost the ability to talk without reading from a slide? I recently had a round of creative reviews, and asked 'just show me the work.' I did eventually see it, embedded in hundreds of slides of explanation. Please stop," he said.
Pritchard also addressed the issue of advertising appearing next to extreme content online. Last week, YouTube announced it will use third parties to provide 'brand safety' reporting, and Google has previously apologized to advertisers for ad misplacement on the video site.
He said P&G would "clean up" its relationships with media suppliers, and added that he had a zero tolerance policy regarding ads appearing next to "objectionable" content.
"Here's the head fake you might get: 'But you've only had a couple thousand impressions served on objectionable content…' Response: 'That's a couple thousand too many.' We have a zero tolerance standard when it comes to brand safety.
"Our brands are protected in other forms of media. The same zero-tolerance standard of performance applies to digital media."
Pritchard has previously called the media supply chain – the companies involved in buying advertising space on P&G's behalf – "murky at best and fraudulent at worst."
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