Thanks for your reply. So even at Microsoft developers have to write documentation themselves ? There are no technical writers to help ? I do not know how to catch up with the documentation now there are tons of undocumented code - your ideas are great for ensuring the situation won't reproduce but I need to catch up too. Thanks.
So for public facing documentation on an API there are technical writers (like for support docs) but for internal documentation we are expected to keep code well documented. Yeah it might be good to just start having these safeguards and as the code base churns it will gradually get fixed.