Why do a POD? The most common reason is to avoid probate. This allows the transfer to occur very quickly (usually a matter of weeks if not days) and avoids fees associated with probate.
I do see clients who go overboard on PODS, creating so many that there are no assets in the estate when they die. Yes, that means they avoid probate. But they've also created a situation where the question is raised - who is going to pay the final medical bill, credit card statements, etc. Sometimes it is a good idea of have a small amount of money left in the probate estate to take care of those final expenses.
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