"It can be easy for pay-per-use models to get out of control and become very difficult to forecast," Staten says. "But with the concept of rollover minutes, enterprise customers can forecast a monthly expenditure and float services throughout the year."

Staten says vendors must also analyze what they do best and market those skills to a new wave of IT buyers looking to blend smaller sets of services with their own internal resources.

"We are already seeing it with bigger traditional outsourcers, which are being more selective with the services they offer," he says. "But others will have to learn as they get trounced by competitors that specialized in a set of services and helped the enterprise become much more efficient."

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