These models were "invented" for non-technical types like MBA monkeys to help them feel like they are in control of software engineering process. If you look at these models closely, you realize they resemble various principles employed by mechanical/civil engineering.
So what we have here is the attempt by non-technical managers, to bring some "feel" of control over something inherently complex (software development), modeled by their semi-successful methods of management employed in traditional industries (read companies like GE).
What those guys fail to realize is that software engineering is fundamentally more complex and, therefore, unpredictable than manufacturing industry they're used to (from their business school books).
So what we have here is the attempt by non-technical managers, to bring some "feel" of control over something inherently complex (software development), modeled by their semi-successful methods of management employed in traditional industries (read companies like GE).
What those guys fail to realize is that software engineering is fundamentally more complex and, therefore, unpredictable than manufacturing industry they're used to (from their business school books).
Pathetic.