Exactly.
Two main components necessary for successful software development are engaged customers and a system for engaging the customers. Agile is the latter but does not guarantee the former. If the customers don’t know or can’t decide what they want, they still won’t even if you’re Agile.
Also, many systems interface with other systems that for various reasons (complexity of implementing changes, or a rigid COTS system) cannot be changed rapidly, and so any rapidly implemented changes to the Agile part of the equation will only be window dressing since interface changes only move at the pace of the slowest players.
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