There are certain things that cannot be distributed through a will. These are called nonprobate assets. Examples include death benefits like insurance, assets already held in a trust, etc. Think of it this way—assets that already have pre-determined and legally sound ways to be distributed outside of a will cannot then be included in a will. If you have life insurance, for example, you determine beneficiaries of the policy when you create it and can modify those beneficiaries during your life. When you die, the life insurance is distributed according to your decision as communicated to the life insurance company. This cannot be changed or overridden by a will.