It happened again today. Every time an online service like Twitter or Facebook hits a roadbump, or stops working altogether, there’s an outcry of protest from its users. Then, just as quickly, comes the backlash: “How dare you complain about a FREE service?”

At one level, I understand the thinking: there is an army of developers, sysadmins, designers, administrators and other great people who work hard to conceive, create and maintain the web apps. And behind that, a lot of money is being invested.

On the other hand, there’s another kind of investment being made in these services, and that’s the time and content that you and I put into participating: the photos we post to Flickr, the videos we share on YouTube, the hours we pour into Facebook – and the millions of observations, complaints, links, updates, insights, jokes, memes and random stuff we tweet on Twitter.

That effort doesn’t just represent an opportunity cost on your part (you could be spending that time working out on your Wii, for example) – it represents value to the owners of the web service you’re using. Facebook’s business model involves delivering highly-targeted eyeballs to advertisers, as does YouTube’s. And while nobody’s quite sure what Twitter’s business model is, it isn’t philanthropy.

Look at it this way. If Twitter was nothing more than its hardware and software, does anyone seriously think people would be bouncing around multi-hundred-dollar valuation estimates?

The implicit bargain between social application provider and user is this: they’ll provide these amazing tools whenever and wherever you want them, and you’ll provide the content, conversations and relationships that create value and help them realize a return on their investment: financially or (in the case of reflected-glory marketing) in brand equity.

Now, most of us understand that these are still early days, and sites will have the occasional hiccup. But when repeated or lengthy outages seriously impair our access to tools, people and content – especially when those outages come without an explanation – then our patience rightly wears thin.

So if you’re a user on a social web site, do cut them some slack (especially during a denial-of-service attack)… but don’t feel you have to apologize for feeling irritated over repeated fail whales and error messages.

And if you’re running a social web site that’s running a mild fever or fending off a cough, thank your users for their patience, explain what’s happening… and do what it takes to get back up and running.

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