In any organization, there's an element of accountability and responsibility. If things go wrong or decisions need to be made, there's invariably a chief or boss that is able to say "the buck stops here" after you (as a customer, or member of the public that might become a customer) ask a question or have a complaint.
For reasons I will lay out here, this doesn't always translate into Social Media. Social Media strategies often get pigeon-holed into something other than "engaging with customers and potential customers". From a corporate standpoint, a SM strategy sits straddling the boundaries between customer support, advertising and sales.
The mistake that is often made is rather than straddle this line, it's parcelled off to third parties who know how to do one thing only.
We see "advertising", where you end up with an ad agency running a Facebook page for brand awareness on behalf of the brand that's visible to the consumer. This means that should anyone have an issue with the product, there's no hierarchy of responsibility on the part of the advertising agency to escalate the customer issue to the chief that might be able to resolve it. This invariably leads to disappointment, and in some cases the whole social media strategy inverts on itself and becomes a farce that has to be taken down quickly as a measure of damage control.
We see "sales" in situations where social media accounts run by sales lead generation companies, and these people don't have customer support ties either. What can happen here is often tantamount to the situation we see with advertising.
With "support", we often see third parties brought in to clear customer enquiries, but they have no tie-in to the sales side. This leads to situations that I normally call an "Order Prevention Desk", because as a customer you find you literally cannot give them your money.
The only way social media can work from a corporate or government standpoint is to put in a social media advocate that can receive escalated issues that arrive via Twitter or Facebook, and then direct them up the traditional hierarchy to the same people that would have been responsible for the same enquiry had someone approached them using traditional methods.
What has been proven is that abandoning this chain of command generally leads to disappointment.