When you buy a new computer, you get a free antivirus software along with it which is only for a limited period of time that is either for 30 days, 60 days, 90 days or 180 days or more depending on the antivirus that you got.
After the free antivirus is about to get expire you will start getting an update request.
Many users ignore the antivirus protection expired message. But they are unaware of what may happen to their PC if they do not update the antivirus software.
The Microsoft Malware Protection Center has found having outdated antivirus software on their PC or not having any antivirus can risk their computer.