Why is Agile such a Hard Sell?

Did you ever try to sell Agile development to the upper management? How often did you encounter a response similar to "That's not how it works in the real world"? I came across this in numerous conversations, with members of every level of the organization, from programmers, to team leaders, to PMs, to marketing to CEOs. It seems to me that the entire gripe everybody has with Agile is centered on the Iron Triangle: The customer wants everything he asked for, exactly when he needs it, and the budget is exactly what he's willing to pay.



Every single agile development methodology I've come across, states in no uncertain terms that they (they being the customer, management, marketing, PMs) simply can't have it. The agile proponents say things like "it will be ready when it's ready" (very bad for business), or "We'll deliver what we can by the deadline" (not very good for business, either).

So, for the non-agilists out there, it's a no-brainer. Up until those crazy extremos and scrum-masters (what the hell is that?!?) came along, we could tell the developers how long they had in order to develop the system we require, and come hell or high water they would burn out the candle on both ends, working nights and weekends to make the deadline. Kindly take your "Agile" and stick it where the sun don't shine!

What management conveniently ignores, is that most of these commitments are never met. And if the software is out the door by the deadline, the quality sucks. Why is that? Quite simply because there are no free lunches. Resources * Schedule = Scope. In otherwords, there's no breaking the triangle. Management is simply used to a methodology hinged on wishes. The way I see it, Agile is the proverbial messenger being shot for exposing the truth of it.
PMs often prefer to get forgiveness, or figure out how to shift the blame, for missing the deadline, than to get the permission to do so. I wonder how many clients would agree, if the software shop asks them: "Is it okay with you if we lie about our abililty to deliver all of this by the deadline, with what you're paying"?

What Agile methodologies such as XP and Scrum truely does for business, what really needs to be emphasized in an elevator pitch, is that they offer a solution to the problem agile exposes. By focusing on delivering, in high quality, what the customer needs most, by enabling changes further down the line, deadlines can always be met, by delaying the release of low priority features.

What do you think? Are there other reasons that managers dislike Agile?