I've personally seen countless estate planning documents. I've reviewed everything from the most robust, well-drafted masterpieces to the cheapest template forms recycled over and over. In the last few years, I have come across more and more documents that people create themselves from online discount websites.
I can certainly understand that DIY can save both time and money. Especially around the holidays, it can be a very tall task to schedule an appointment with an estate planning attorney, spend 30-60 minutes preparing some information ahead of time, and then carve out an hour to meet in-person with the actual attorney to discuss your estate planning. Wouldn't it be easier to just sit on the couch and type your credit card information into a website after the kids went to bed?
Speaking of credit card information, a good estate planning lawyer can be very expensive! LegalZoom or RocketLawyer can give you an "estate planning package" for a few hundred dollars. An experienced estate planning attorney will most likely charge multiple thousands.
I recently browsed a couple of these websites. One website had misspelled words, an incorrect name for an estate planning document, and had two different "packages" that were missing at least one (or more) of the essential documents that EVERY ADULT needs in their estate plan!
The websites also advertise that attorneys are available to assist you, but that is rarely the case. Usually, there is no advice or counseling given at all (or you have to pay extra for it, which people will usually skip).
What if you don't even know which questions to ask?
One of the big problems with DIY estate planning is that you may never have an opportunity to fix any mistakes. When you try to work on a home project yourself, when things don't quite fit the way they are supposed to, you know it right away. You have an opportunity to make it right. The same goes with your taxes. When you file taxes, if you make a mistake, the IRS will send you a letter (usually asking for more money) and you will work it out with them.
The protections of your estate plan usually don't need to be implemented until someone becomes ill or passes away. Once that happens, those you leave behind will find out whether or not your plan will work properly when needed. Unlike some of the other DIY scenarios, it is usually too late to fix any mistakes by the time the mistakes are uncovered.
In conclusion, my warning is one of caution. You get what you pay for (which may not always include any legal advice). There is probably a good reason that these DIY programs include a lot of fine print disclaimer language and "terms of service" that you need to agree to before they will allow you to download their fill-in-the-blank templates.