"Do the Right Thing".
Ten Serious Mistakes to Avoid in Estate Planning
4. Failure to Coordinate Beneficiary Designation with Your Will.
The will provides a thought-out estate plan, complete with appropriate tax planning. But when the attorney starts investigating, he finds that the person’s estate plan does not work. Why? Because a substantial portion of the person’s assets pass by operation of law (such as by beneficiary designations) to persons who were not supposed to receive the property under the will.
It is not sufficient to merely write a will. Beneficiary designations must be reviewed to make sure that someone who you no longer wish to inherit does not receive property, that no one receives more than you intended, and that enough money is available to fully fund any bequests that you wish to make in your will.