I've seen the following scenario unfold at two different clients:
1. Initial enthusiasm to go Agile, driven by an executive mandate.
2. A mix of eagerness shown by some delivery people (devs, QA, analysts, PMs etc.) and resistance by others.
3. Growing friction between the two factions, inducing the executive management to create layers of Oversight Committees, PMOs, Steering Groups, Agile Coaches / Coordinators / Evangelists / Czars / Sensei / Black-belts -- and other holders of titles culled from clergy, industry and fantasy.
4. Adoption of the easier Agile habits: story-walls, open work-spaces, iterations (sometimes not time-bound) and stand-ups (sometimes modified to sit-downs).
5. Assiduous proclamations of the merits (equally often, the demerits) of the harder Agile practices: independent stories, independent estimates, TDD, CI, automated test suites, tracking delivered business value (using PM tools appropriately) and continuous customer collaboration.
6. Permeation of a snarky disbelief throughout the organization in the viability and usefulness of Agile practices.
7. Recidivism to the previous state of suboptimal software delivery, while retaining the glittery Agile titles: people, processes and productions glow with the newly acquired veneer of Agility while losing none of their inner fragility. I've seen 40 minute long meetings (with less than 10 attendees) conducted in the name of a "stand-up".
This scenario -- which I dub Cargo Cult Agile Adoption -- reveals a belief that simple mimicking of some externally visible Agile practices will somehow create the values that underlie those practices.
The ritual of having a card-wall cannot create even an illusion of communication, if the will to communicate openly is not there. The ritual of creating a CI server cannot substitute for the values of courage and simplicity -- the CI build will probably be either mostly broken, or developers won't commit any code for days for fear of breaking a brittle build. Rituals and practices are merely the expression of underlying values, they cannot cause those values to exist out of nothing.