I enjoy a good challenge, but I enjoy efficiency even more.
Function before form.
Teddy Roosevelt said, "Nothing in the world is worth having or worth doing unless it means effort, pain, difficulty," which is a great start; but I'm of the belief that there is always a better way.
Let the difficulty of a task lie in the invention of its solution in the cleanest and most efficient fashion. Let the pain of a task be in the dedication and hard work in the pursuit of perfecting its execution.