There are very few incontrovertible laws that govern the business of advertising, but gather round and you may soon have something you can carve in stone next to your desk. Rule one: if a character in your ad expresses surprise with the words "What the ...?", the ad will not be good. When did you last say "What the ...?" as a genuine reaction to something that surprised you? We'll bet our very valuable Stormtrooper Mr Potato Head that the only time it ever gets said is when a writer/art director/director tells some poor actor that it's their next line of dialogue. Try to work "What the ...?" into a conversation and see how long it takes for someone to think you're a tit.
BUCK STOPS WITH PLANNERS
Who's to blame if an ad is ineffective? I don't blame account management that much. Yes, maybe they sometimes fail to sell a great campaign. But not often. I think creatives like to believe that everything they come up with is brilliant. It isn't. Clients sometimes play things too safe, and buy the more conservative of two routes, or water work down, so that it ends up being too boring for consumers to be interested in. So they must take some blame, too. But the group that must shoulder the most blame is the planners. Effectiveness is their explicit responsibility. And it is the strategy that makes the work work, or not work. Sorry, planners.