To improve performance in this area, IT managers should consider establishing an "IT finance function" within their department, Forrester Research has advised.
This function should have wide-ranging powers and help to ensure that IT projects achieve their aims.
It would assist in compiling business cases and track the value of IT investments, according to research by Forrester analysts Marc Cecere and Adam Brown, which was published earlier this month.
Another role would involve checking that there are enough resources available - both time and staff - for new projects.
"From a structural perspective, this [finance] function is best grouped with the planning function within IT," said the research. "However, in some organisations, the planning group focuses largely on the technology architecture and spends little time prioritising IT investments.
"In this case, it is better to have the finance function report as a separate group to the CIO or within a customer-facing organisation such as relationship management."
Forrester also recommended the IT finance function should play a role in overseeing and dealing with suppliers and defining the technical architecture that underpins the IT project.
"The definition of architecture standards needs to include financial implications. In part this is to provide support for what are often unpopular standards."