I ran across an article this morning that deserves a look if you are endeavoring to complete a software development project anytime soon. In summary a study was conducted of 450 organizations to determine how efficient their requirements gathering was and how it affected the overall short and long term success of the software development effort. IAG Consulting found that "One-third of expenditures on development projects are squandered by three-quarters of organizations, because they lack consistent requirements and discovery management processes."
As the article points out, a number of factors contribute to this problem but overall, those companies that employ and agile development methodology are more successful at delivering high quality, successful projects. You can read the Redmond Magazine article here.