One day in Jiu-Jitsu class, Conan joked that he didn't have anything else to teach us, because he was pretty sure that he'd already taught everything he knows. A student responded "Could you please just start over, from the beginning?"
Practicing basics doesn't always seem to be so popular, but it's necessary, and not just for new students. One of the keys to learning Jiu-Jitsu, or any other physical activity, is repetition, and you can never go wrong by working on the basics. It's not always exciting to practice the same things you've done a thousand times before, but that is how you build the muscle memory to be able to perform without having to think about it. The reason we practice shrimping in almost every single class is because it is such a vital basic. Recently while I was rolling with Conan he teased "Wow, you're shrimping like someone who actually knows Jiu-Jitsu!", and I was thinking "You know it's hard out here without a shrimp!"
It may be more fun to practice cool new techniques, but if all you do is keep adding things to your game without taking the time to sufficiently drill them until they become second nature, you probably aren't learning as much as you think. Perfecting the basics gives you a solid foundation on which to expand, so although practicing them may sometimes be boring, it is essential to your training.
"There is no such thing as an advanced technique, just a basic one done well." -Shihan