Whether it’s anti-virus definitions, windows updates, or firmware updates, people constantly fall behind on keeping their computers up to date. If you couple this with doing in-frequent or non-existent backups then you will find yourself in a really bad situation fast!
It’s easy to fall behind, but instead what you should do is make sure you renew your anti-virus and that you run your updates on a regular basis. If you can’t be bothered, there are a lot of automatic options you can set. For critical machines you probably don’t want to update automatically and instead verify the updates you are installing first.
Stay safe, keep updated!