The audience at the Effective IT Summit 2005 responded enthusiastically when asked by Fred Tingey, head of IT at financial services giant BNP Paribas: "How many of you develop your software using the ‘waterfall method'?" Tingey then surprised them: "All of you who are doing projects this way are doing it wrong."
The waterfall method helps software developers break down projects into a hierarchy of stages, activities and tasks, which can then be represented in a so-called waterfall diagram.
The weakness of this approach is that it is a staid, ungainly approach to development, where problems only come to light when it is too late, says Tingey. "Individual parts of a system may work but it is virtually certain that when you put them all together the system will not." Even if it does work, the system created may no longer meet the end user's needs because its rigidity will prevent feedback being fed back in.
His arguments are supported by research firm The Standish Group, which noted that only a third of IT projects in 2003 were successful and the majority delivered half of the initially required functionality.
Instead, software development should rely on agile methods, says Tingey, focusing on iterative development that is constantly aligned to business requirements. This approach helps reduce risk and shorten development times.
BNP Paribas used this so-called ‘agile development' method to get one of it failing IT projects back on track. Eight developers had started a six-month project to create a workflow system for credit requests and limits. However six, including the leader, left within three months of each other.
The project was completed just a month behind schedule, principally because new developers started immediately with testable working software rather than half-finished components. "Everything that works was developed iteratively," says Tingey.