A personal laptop of an employee is a very good entrypoint for an attacker. First thing you do is log in to your job. It may be a vpn, a site login, some token gets stored on your computer for the day. If someone gets access to this, it can be devastating. So, if a vulnerability gets discovered and patched by the OS, it can be very important to update as soon as possible. So companies scan their empoyees laptops, is one thing, and if the try to connect they also try to check that the computer appears up to date, is known, and so on.