There's an old saying that a shadetree handyman has only one tool in his toolbox: Duct tape.
Some in the agile community seem to be turning into shadetree handymen. They've got a single model for agile work that they apply to every situation. When all you've got is duct tape, everything looks like a duct. Often duct tape is just the right thing. But sometimes, chopping a duct into a bunch of little iterative ducts restricts air flow. In his enthusiasm for duct tape, the handyman may forget the goal is to promote air flow, and not (necessarily) just to iterate the ductworks.
There's been a lot of interest in the past couple of years in applying lean principles to software development. Lean and agile thinking are compatible and complementary. There's an approach based on customer pull and single-piece flow that is becoming popular under the name "kanban," although kanban as such isn't the whole process. James Shore recently published a very clear and concise description of a kanban process for software development. He also offers some suggestions about when to choose an iterative process and when to choose a kanban process based on key characteristics of the situation at hand.
It's good for the shadetree handyman to add a second tool to his toolbox: WD-40. When duct tape makes things stop, a bit of WD-40 might make them go again. The trick is to know when to apply each tool.
In the beginner's mind there are many possibilities; in the expert's there are few.
— Sunryu Suzuki
