In the US the Waterfall development mirrors the current government procurement model (Contracting Process) and the POM Budget Cycle – (see OMB 300s) AND THIS IS A LONG PROCESS…
- The Budget cycle is built based on horizon of predictability. The Budget categories reinforce long stage-gated development cycles and force funding requirements well in advance and requirements to be produced up front
- Agencies document their needs extensively, and such requirements are easily incorporated into a solicitation
- This up-front documentation allows agencies to safely budget funds and allows contracting officers (COs) to marry funds to specific, pre-defined contractual events
You have to recognize that this process is law and it’s outlined in the Federal Acquisition Regulation (FAR). Hence the bureaucracy that this creates is quite enormous.
To do a good job budgeting the process forces agencies to have detailed requirements/technical specifications prior to a solicitation hence the reason Waterfall becomes the default.
If you really want to be scared, here is a pictorial of the DOD’s procurement process: The fear for your tax dollars link