One of the things I review is how complete and thorough the documents are. Sometimes, the documents are rock solid - they are comprehensive and really capture what the clients are trying to accomplish. Other times, they are decent documents but they don't capture what the clients want. In other words, when I tell the clients what the documents say, the clients will often say, "We don't want that. We didn't know that was in there."
There are times when the document are entirely inadequate. However, what I find more often than not is documents that aren't bad....they just leave too many things to interpretation. Also, many important issues to the clients are either entirely not addressed or inadequately addressed. Those "holes" in the plan can lead to trouble.
You see, in many cases, it's not what the documents SAY that is the problem. It's what is left UNSAID that can be the problem. Therefore, it is important to make sure that your documents say exactly what you want them to say. If something is important to you, the documents should address that issue. You also want your documents to address important variables that can occur - some are more common depending on your family situation. If your documents are silent on important issues like what to do with the home after you pass away, how to care for a certain individual in your family, or whether people should inherit directly or in stages, etc.
When a living trust or other document is silent on important issues, it leaves too much to the imagination, and that's where families get into trouble. When people can't agree what to do and the documents are silent on a particular issue, that just leaves everybody in a state of confusion.
Certainly, there are families that get along in every respect, and everyone agrees on everything. However, that is probably the exception and not the rule. If people differ on how to handle the estate and the documents offer little direction as to what to do in certain circumstances, entry-level estate planning documents aren't going to offer much guidance. Therefore, sometimes I tell clients that there's nothing actually "wrong" with their documents per se. It's what the documents leave unaddressed that is often the problem.