When you have a large estate that includes significant assets, writing a will is a necessary piece of your overall estate planning. If you die without a will, how your assets are given out, and the fighting that can ensue among your family members, can become a logistical nightmare. When you don't have a will in place to give away your assets to heirs that you assign, your estate can end up stuck in probate court for years while potential heirs wait for their inheritance.