What's the worst that could happen, Coca-Cola began asking teenagers nine years ago as part of an edgy initiative to tempt more of them to try its Dr Pepper brand.
Well, how about having to make a public apology after abandoning a Facebook promotion that led to a girl of 14 trying to watch a pornographic movie trailer featuring two women having fetishistic intimate relations?
Furthermore, Lean Mean Fighting Machine, which devised the promotion, has been forced to end its work on the Dr Pepper and Coke Zero digital ad accounts.
Many might argue that - for client and agency alike - it couldn't get much worse than that.
Yet it might well do so, and not just for Coke. As advertisers venture further into social media, so the cock-up quota will rise, onlookers believe. This is mainly because of widespread ignorance, particularly among mainstream agencies, about the risks involved and at what point the acceptable ceases to be so.
"It's easy to point a finger when online promotions like this go wrong, but the fact is that people are very confused about what they can and can't do," Molly Flatt, who runs the word-of-mouth specialist 1000heads and is the president of the Word of Mouth Association UK, says. "The expansion of social media is going to throw up a lot of complex issues and I believe that the kind of thing that happened with Dr Pepper is going to become increasingly common."
Social media specialists believe that trying to clean up the mess caused by a failed campaign is no substitute for ensuring you avoid making a mess in the first place.
Although promotions on Facebook count as advertising in paid-for space and are subject to the Committee of Advertising Practice codes, WOM UK admits it is alarmed at how little its members know of the rules regarding issues such as consumer engagement, transparency and privacy.
"When it comes to social media, we're all pushing at the boundaries," Ivan Palmer, the chief executive of Wildfire Word of Mouth, acknowledges. "We've codes of ethics covering everything from TV advertising to direct marketing. It's very important best practice extends to social media."
Not least because damage limitation from marketing "own goals" is becoming harder than ever. "Once upon a time, if you got something wrong, you'd get a few letters of complaint and you'd deal with them," Jeff Dodds, Virgin Media TV's brand and marketing director, says. "Now social media means one protesting customer can quickly get an audience of millions. A small issue gets amplified into a massive issue that you can't contain."
Whether or not an agency should lose the account, as LMFM has done, when a Facebook-type fiasco occurs is an open question. "It's beholden on an agency to promote best practice," Palmer says. "If a client wants to do something differently, it's up to the agency to point out what the risks might be."
In the end, saying sorry in the most public way possible seems to be the only option. "Making an apology is pretty much all you can do," Flatt advises. "Admit the mistake and take the rap. Should the agency resign the business in such circumstances? It might just be the honourable thing to do."
And, ultimately, don't ever be fooled into believing that any publicity is good publicity. "That's never been true," Nick Blunden, Profero London's chief executive, says. "Just ask BP."
AGENCY HEAD - Nick Blunden, chief executive, Profero London
"One way of minimising the damage caused when a social media campaign goes wrong is to draw up contingency plans - as we do with our clients - to pinpoint any potential dangers in a campaign and to agree beforehand what's to be done if trouble arises.
"Of course, this can never be an exhaustive list - social media takes marketers into places they can't control - but it's good practice to do it.
"If the worst happens, it's important that clients and agencies are genuine in their apologies. It may not repair the damage, but it protects your credibility."
AGENCY HEAD - Mark Collier, founding partner, Dare
"When approaching any campaign that has a social media component, expect it to go wrong - because it often does - and think about the worst-case scenario.
"Then have pre-prepared plans in place to deal with possible eventualities.
"The phrase 'the devil is in the detail' is totally apposite when it comes to social media. If you don't get the detail right, it can break you.
"If things do go wrong, approach the issue head-on with complete honesty and transparency. Delays and half-truths will only increase speculation and negative chatter.
"Most social media cock-ups have a short lifespan. This can be made shorter by fronting up immediately."
CLIENT - Jeff Dodds, brand and marketing director, Virgin Media TV
"When it comes to social media, we're all learning as we go along. That means risks will be taken and mistakes will be made.
"When that happens, you have to be honest and admit you're doing new things and that sometimes you'll get it wrong.
"Clients don't have the time to keep up to speed with everything that's happening in social media. That's what their agencies are paid to do.
"There's no black-and-white answer to whether an agency should be fired after something like this. It depends on how good the relationship is - and how catastrophic the cock-up."
SOCIAL MEDIA SPECIALIST - Molly Flatt, WOM evangelist, 1000heads
"Your alarm bells need to be ringing if you're planning to go into social media to communicate with teenage girls. You must think carefully enough about the people you're going to talk to.
"If a campaign like this goes wrong, then your best option is to take the rap for it. Somebody senior within the company needs to be on YouTube explaining what went wrong and how it happened. You have to avoid the temptation to sweep it under the carpet.
"It may be that when something like this occurs, an agency needs to do the honourable thing and resign the business."
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