Technology changes so rapidly that tackling an IT project spanning five years is like writing a wishlist, the CEO of the Project Management Institute (PMI) Gregory Balestrero said.

Speaking at the Forbes Global CEO Conference, Balestrero said projects fail due to a lack of clear design requirements and project scope.

To prevent projects from becoming unwieldy beasts, he said IT needs a disciplined approach to management throughout the lifecycle of the project.

"Technology changes so rapidly; how could you have a five-year IT project, unless you constantly stay focused not only on the original requirements and scope but also ensuring the products used will mirror technology as it is today? A five-year IT project is a wishlist," Balestrero said.

"Back 10 years I think there were two situations - IT as an infrastructure was moving into relational databases and there was still a high silo of technology in business and at the same time the Internet was exploding - people were pouring truckloads of money into IT initiatives that had no strong business case and projects were over valued eight, 10, 12 times their initial investment without any real business case to achieve success.

"The combination of these two factors as the dotcom business collapsed changed the way people were looking at IT. I think there was far more attention paid to the need to succeed in projects and to let business drive IT so IT had to become part of the business solution, not necessarily the driver of change."

Balestrero said project management is gaining acceptance within the IT industry due to the demand for more accountability and ability to manage risk.

A recent PMI study of 225 C-level executives in the US, Europe and Asia Pacific found 78 percent rank project managers on par with, or above, other strategic functions like legal, finance, marketing and information services in terms of the value provided.

Managing director of specialist project management company RNC Global, Diane Dromgold, said the best way to deal with scope in IT projects is recognize that it will always change, and the job of a project manager is to manage what the client wants, not what the project should be.

"The problem with project management is that project managers want to lay down an implementation path and they get grumpy if the project differs from that," she said.