Understanding the two phases of a Windows update is crucial. The two stages are downloading the update and its subsequent installation. If you turn off your computer after the update download is in progress, there will be no harm. But there would be two outcomes in this scenario. Your computer will either back up or store the data that was acquired until the point it was permitted to run, and the download will continue from where it left off. If you shut down your computer while the update installation is in progress, chances are that the process will come to an end. When you turn on the PC after its abrupt shutdown, the installation process can take some time, and there may be a few delays in updates. The time taken for the installation depends on your system settings, the quantity and nature of updates, and your system configuration. So, the best thing to do is never to give your PC a chance to turn off while an update is in progress.