A potential new client asked me this on a video call a while ago, not in an accusatory way, but as a genuine question.
Like a lot of services, there are companies who will write your Will cheaply or even for free, so why should you pay a couple of hundred pounds for a professional willwriter to do it for you?
Well, we all need to get paid, so if someone is doing something for free, you have to ask yourself when they will eventually get paid. In some cases, solicitors write Wills for free but appoint themselves as executors, therefore guaranteeing (unless the Will is replaced in future) themselves a bigger payday down the line. This appointment prevents the family from being able to shop around for the best deal in sorting out their relative's property, after their death.
Or there's Free Wills Month, as above. Well, the only person I know to have used Free Wills Month had a solicitor come round to her house, and frankly, he didn't appear very interested. This wouldn't happen in all cases, but if he truly wasn't getting paid, he seemed to not put the effort in.
Going on to cheap internet providers or the Post Office Will pack, I've looked into a couple of these, and like many sectors they seem to not give too much (if any) actual tailored advice, and thus they rely on the client having a bit of background knowledge. You may have some knowledge of Wills; most people do not. I certainly didn't before I got into this industry. Some companies offer to write your Will for £30 - for £30, how much time and effort will they put into one of the most important documents you will ever sign?
A Will is not something you want to mess about with, simply because it's not like you buy a shirt, get home and find out there's a hole in it so you take it back to the shop. By the time you find out that the Will doesn't do what was intended, the person is dead and it's too late: either the Will does the wrong thing or it is cancelled, and the law takes over, and the law does not respect a person's wishes.
Better just to get it all done properly in the first place.