Your Will is only one of many tools needed for a complete Estate Plan.
A will is a legal document that provides your instructions regarding what you want done after your death. This includes instructions for your funeral, for your family, but mostly people consider how it applies to your property. Remember however that this only applies to your property that has not already transferred directly through other means such as Beneficiaries, Transfer on Death, Pay on Death, or other legal means to automatically transfer your assets when you die. Any property passing "outside of Probate" is not affected by your will and can leave your heirs with very uneven inheritance amounts which was not your intention. A properly drafted will is only one of many tools we use for a comprehensive estate plan.
The Probate court will use your will to legally transfer any assets that did not automatically transfer through those other legal avenues. If there are challenges to the Will, Creditors, or other problems the Probate court will use your Will to try and determine your intentions and transfer property legally under the law. This is where a poorly drafted will can be ineffective if it does not legally identify the property, how and to who it will go and what happens if that person has already died before you. Other issues can occur in situations where the Will has not properly addressed situations that can arise leaving the probate court to only guess as what you want done. Make sure your intentions are able to be effectively carried out by a complete estate plan.
Proper Estate Planning includes a Will as only one of many tools needed and certainly not the most important one in drafting a proper Estate Plan.