At the latest when our computer restarts by itself, we realize that we should have had the new update installed a long time ago. As a user of Microsoft products you might expect that such an update can take longer. Occasionally, it also causes various applications to no longer work the way you're used to (IOS updates probably cause problems as well). However - I assume - not to the same extent as Windows updates. I'm not at home in the Apple world). That is why we often tend to comply with this request to reboot and install at the latest possible time. However, from an information security perspective, this is quite risky. Because regardless of whether it's the operating system of a laptop, PC, router, smart TV and other (supposedly) smart devices, they are only best protected against external attacks if the systems are up to date.
When patching, IT companies eliminate security gaps - also known as bugs - or add functions. This does not require the device or software to be rebuilt. Security vulnerabilities are weak points in a program that can be used by potential attackers, e.g. to introduce malicious programs. As a result, the attackers can take control of your systems (the latest security vulnerabilities are published by the BSI, among others: https://www.bsi.bund.de/DE/Themen/Unternehmen-und-Organisationen/Cyber-Sicherheitslage/Technische-Sicherheitshinweise-und-Warnungen/Cyber-Sicherheitswarnungen/cyber-sicherheitswarnungen_node.html, opens an external URL in a new window). On so-called "patch days" (usually monthly), the manufacturers provide updates that are then usually executed automatically on the end devices. By installing these updates, the devices are well protected against external attacks. That is why it is important to run these updates as soon as possible.
Under Windows 10, the current update status can be checked via the "Check for updates" application. In the best case, your own computer is up to date. This means that all known vulnerabilities have been fixed. If you are missing updates, I recommend that you install them as soon as possible.
The "Advanced options" button should also be used to ensure that all updates provided by Microsoft are installed and corresponding notifications are displayed.
If you use an Android smartphone, you will find the menu item "Security" (or "Biometrics and security") under the device settings. There you can check for new updates and have them installed if necessary.
Feel free to leave questions and suggestions about the topic in the comments here at coLab. I will be happy to respond to them.
If you use a TU.it device, updates and patches are installed automatically. More information can be found under the service "TUclient" at the following link: https://www.it.tuwien.ac.at/en/services/workstation-support/tuclient.