Some people think that doing things “agile” means all you need is: a client that will never get pissed off, a set of loose requirements and eternity for development work. These people are wrong. If you think I’m lying, you belong to the same group of people, what implies that you’re wrong as well. As easy as falling off a log.
If you’re dreaming of a zero-day-millions startup, you’re not willing to learn and your ego is much greater than your skills, you would probably use “agile” buzzword so you’re very likely to hide your incompetence. “What? What documentation? Diagrams? UML? What is that? Come on, we are agile, you silly boy! We create coolest Web applications with no effort at all!” Don’t do that. It’s wrong.
Production is still production, no matter how much fun you think it is and how relaxed you are. Especially software development is the area where thinking, designing and planning is a serious job. And, let me remind you, building Web applications is software production. No matter you like it or not.