A will is a necessary estate document. It spells out your wishes and lets your loved ones know what you would like to happen with your assets after you die. It can cover many things, even non-financial wishes.
Still, the American Bar Association explains there are a few things your will cannot cover. These are either items you cannot include in a will because there is another legal point that covers them or things that, if you include, could cause some issues during probate.
You cannot will a loan to someone. You do not own the loan, so it is not your property. The bank has all rights to the loan. When you die, if someone wishes to assume the loan, they will have to go through the lender to do so. You cannot pass on that contract.
If you have an account with a beneficiary, you can note it in your will, but you cannot change who will receive the money. You would have to do that with the account manager. For example, if you have life insurance, you need to make any beneficiary changes with the company. If you try to do it in your will, it will not stand up in probate.
You cannot change the title of owned property. You can leave property to someone, but the title change must occur after your death and is the responsibility of the heir you left it to.
Your will cannot override existing legal agreements. It cannot supersede the law either. You should be sure that you have the right to make a claim or give a direction when creating your will, which is why it is important to have a legal professional review the document for you.