Shared Services...
is a bit like communism.. It looks good on paper.
Unfortunately it doesn't work very well unless you have a dictator on top that is willing to shoot people if they don't do as they're told.
If you have that, then you can turn a country of serfs with plows to a superpower with nuclear weapons.
Ok, so the comparison is horrendously flawed, but the problem with Shared Services is that most implementations allow the 'participants' to get 'step-outs' from the shared process, meaning that in stead of a dictat.. sorry, director, telling them that they can all just shut up and that all their services will be delivered _THIS_ way, they all decide that the Shared Services organisation will continue to deliver the services they need in the same old format as they've always had.
And that is when you get 1 Shared Service Organisation, with X different departments delivering those services in X different ways. And because those departments are now split from the 'mother' organisation that they service, they become less efficient, and because their office space and resources need to be separated form the 'mother' organisation the whole bloody mess ends up costing a lot more than simply doing nothing in the first place.
The Solution: Shoot the first bloody manager that utters the word 'Shared Services', OR, shoot the first bloody arse that says the word 'step out'.
Either way, it's surprising how well things go when you start to consider this fast tracked method of terminating employees.