Should you choose to utilize a will to elucidate your final wishes the estate will be administered under legal supervision. The probate court of your residence is charged with the responsibility of overseeing the administration of your estate.
The will may seem like an operative instrument, and it is in the legal sense but is after all just a document. Someone is going to have to actualize the instructions that are elucidated in the will and take care of other matters. These would include identifying and retaining a probate lawyer, satisfying creditors, paying final taxes, and inventorying assets in preparation for distribution to your heirs.
All of this is done by the executor of your estate, who is sometimes referred to as a personal representative. You name your choice of executor in your will, and if you don’t the probate court will appoint a personal representative. As you can see the executor has a lot to accomplish, and it is time consuming and requires a good bit of business acumen. So even if you have a friend or family member who is business savvy enough to handle these responsibilities in theory, does he or she have the time?
In addition, if you have never interacted with the probate court you have no idea how the process works. You would have no reason to have existing relationships with appraisers, liquidators, and accountants.
For these reasons many people choose to appoint a professional executor. The trust departments of many banks can and do fill this role, and there are attorneys who are willing to act as executors as well. Whether or not you should seriously consider naming a professional executor largely depends on the size and scope of your estate and whether or not you know anyone who would seem qualified and willing to take on these responsibilities.