UAC is a very important feature in Windows which should be enabled at all times.
If a user grants permission for a program to be executed with Administrative priveleges, it can actually disable UAC since it would have the priveleges to do something like this. So one mistake could end up to multiple processes running with the same rights as a process running with Administrative priveleges.
People need to be a bit more careful, and make sure they don't disable it. As well as this, make sure they know what they are granting Administrative priveleges before they do. Because for all they know, they could be granting the permission to a bootkit.
Good Security software is necessary to be installed on the system to help protect the user. Of course no Security software is bullet proof. Windows Defender is not going to be the best option when you are coming across threats like Cryptowall. We can see this from the amount of people who have been affected by Cryptowall, despite whether they are a beginner or advanced user.
Thanks for the video
@cruelsister.