Pure[1] waterfall is doomed from theoretical point of view. You cannot control a system without a feedback loop, unless you have a 100% accurate knowledge of system's state and future evolution. Waterfall lacks feedback loop => you can't really expect much from it.
[1] - in real life there's always some kind of feedback loop in the process; I'd argue that the primary reason why Agile methodologies seem to work better is that they have a much, much tighter feedback loop than waterfall.
Pure[1] waterfall is doomed from theoretical point of view. You cannot control a system without a feedback loop, unless you have a 100% accurate knowledge of system's state and future evolution. Waterfall lacks feedback loop => you can't really expect much from it.
[1] - in real life there's always some kind of feedback loop in the process; I'd argue that the primary reason why Agile methodologies seem to work better is that they have a much, much tighter feedback loop than waterfall.