To make a memoir worth reading, they must be engaging. Which means getting personal. I recently read a statement to the effect that for a memoir to be interesting, it must border on embarrassing. In other words, revealing.
I have tried to re-find the quote I read about memoirs needing to border on embarrassing so I could quote it directly here. I couldn’t find it, but I found a post by another person that reveals components of a good memoir. Check out what Jeff Goins has to say about the components of memoir writing here.