Many agilest use Waterfall as the Boogeyman of software development. They show pictures of Design-Code-Test process, with no feedback loops, linear connections from beginning to end in the project.
Here in the DOD, Waterfall went away long ago as an acquisition strategy. Here's one of many guidance documents. Waterfall is dead, stop using it as a whipping boy. If you're doing waterfall in your enterprise IT, you're doing it wrong. Stop and learn how to apply modern techniques, one of which is Agile, but there are others. Google dod 5000.2 procurement agile to see how it's done.
