I was reminded last week of a concept from Steven Covey's book "Seven Habits of Highly Effective People." It's the idea of categorizing tasks as urgent/not urgent and important/not important. I'm usually pretty good about taking care of things that are urgent and important. It's the not urgent/important tasks that I put off. I've found that estate planning falls into the not urgent/important category for many people. It's something they know they need to get done, but there's no sense of urgency.
There was a client at my old firm who loved to purchase properties at tax lien auctions, and had over 100 properties. The story goes that he told his family that all of the information about the properties was in his head and he'd eventually get around to taking care of his estate planning. He didn't get around to planning before he died. The family was left with a huge mess as they tried to discover all of the information that their father had kept to himself.
Because life is so unpredictable, estate planning should not just be important. It should also be urgent.