Lorenzo Barberi posts this story of a guy trying to introduce agile methodologies into a traditional corporate 'Waterfall' management culture. What's really interesting in this story are the 'lessons' he mentions:

1) I wasn't very good at defending agile practices, which probably made me seem less competent and less professional than I would have if I had been able to rattle off responses to challenges immediately. That's partially a matter of education, an area where I have gotten better, and partially a matter of my personality (INTP) where I almost effortlessly try to adopt the frame of reference of my opponent.

2) I should have been more gradual in my introduction - I should have started with more up front planning and structure, if for no other reason than it would have made the agile thing easier to swallow.

3) I didn't adapt well to the corporate culture, try as I might (and again, because I am an INTP, I tried _very_ hard).

4) I was in a situation where I had very little control over the inputs to my team (in terms of work, etc), but I was expected to keep everything flowing smoothly and sedately down the river of delivery. This was essentially impossible, and rather than ruin my mental health, my car and my home life, I should have walked away sooner.

It is DEFINITELY worth reading the whole post though. I can totally identify with this, although I haven't been through this myself I've always taken issue with the 'Waterfall' approach (to the point of having left previous jobs because this system caused so much hassle).