And it's such a cop-out--I'm just going to redirect you to another good post from Ikigai blog, that is a compact and thought-provoking little piece on kata. I think the biggest principle the writer touches on that is too often ignored is the idea that as karate students we should think about our kata, struggle with them, figure out what they're all about and then keep going back to them and thinking about them some more. It's one thing to do the basic mental crunching of learning a new kata, another thing to get to a point of physical proficiency, but that's just the starting point, the jumping off point to learning from the kata.
A kata is like a book; one that explores the experiences and ideas of warriors from past generations. They encompass not just rote movements, but core principles that made these classical combatants so effective. As Hayes Sensei likes to say, “if you read a book many times over many years, the words never change. But if you are growing, the meaning and understanding of the book will grow with you.”