Favorite Agile Principle

There's been a lot of buzz lately in the Agile community about how far we've gotten from our roots. Most of the talk is around the evils of associating specific approaches with Agile; some have gone so far as to say if you advocate a practice as standard for Agile then you've lost your compass. I have some ideas brewing around those ideas. In the mean time, I thought I'd throw out a positive post to encourage people to get back to their Agile roots. My question is simple: What's your favorite Agile Principle?

Mine is easy: "Simplicity -- the art of maximizing the amount of work not done -- is essential". This principle is elegant and so applicable to my life. I am constantly over-complicating my life, so I've made this principle my mantra to keep me in check.

I understand that all of the Principles are important, so don't get hung up on the question. I'm not asking which one is best or most "Agile", I just want to know which is your favorite.

If you need a refresher, they can be found here:

1. Our highest priority is to satisfy the customer through early and continuous delivery of valuable software.
2. Welcome changing requirements, even late in development. Agile processes harness change for the customer's competitive advantage.
3. Deliver working software frequently, from a couple of weeks to a couple of months, with a preference to the shorter timescale.
4. Business people and developers must work together daily throughout the project.
5. Build projects around motivated individuals. Give them the environment and support they need, and trust them to get the job done.
6. The most efficient and effective method of conveying information to and within a development team is face-to-face conversation.
7. Working software is the primary measure of progress.
8. Agile processes promote sustainable development. The sponsors, developers, and users should be able to maintain a constant pace indefinitely.
9. Continuous attention to technical excellence and good design enhances agility.
10. Simplicity--the art of maximizing the amount of work not done--is essential.
11. The best architectures, requirements, and designs emerge from self-organizing teams.
12. At regular intervals, the team reflects on how to become more effective, then tunes and adjusts its behavior accordingly.