But if it does, don't panic – we've got you covered.
One of the more obscure reasons why a Windows update might not be installing is because a virus or some kind of spyware is blocking it: malicious apps like these can often be squashed by Windows security updates, which is why they try and stop the latest patches from being installed on your machine.
Try running a full and thorough virus scan using whatever security software you have installed (you do have some installed, right? If you think your antivirus tool has also been compromised you can download some on-demand scanners, like this one from Microsoft or this one from Dr. Restoring key Windows files and OS options is a lot easier than it used to be, and 'resetting' Windows 10 basically means putting all the system files back to their factory state without touching your personal files along the way (although you can choose to wipe your drive completely if you want).
This can cause issues itself, so make sure your updates definitely aren't progressing at all.
In Windows 10 you can find the Windows Update page by launching the Settings app from the Start menu and clicking Update & Security – if there's something wrong and Windows knows what it is then you should find details here.
On the next screen you see pick Troubleshoot, Advanced Options, Startup Settings and Restart, and you should then see the Safe Mode option appear: try running through the update process again if you can.
A quick search online will give you Safe Mode instructions for older versions of Windows.
The process doesn't affect your personal files or programs, but it may not be available to you depending on how Windows was originally set up.
If Windows' own troubleshooter doesn't work (see step 4) then you can try and carry out the same process yourself manually: stopping the Windows Update service, deleting the temporary files it's created, then starting Windows Update again.
Type "net stop wuauserv" and hit Enter, then follow that with "net stop bits" and hit Enter again.