Antivirus has been promoted for a long time as a product similar to the toothbrush, detergent or car. The popularity of antiviruses isn’t the only reason they’re popular are not without faults.
It’s not feasible for antivirus programs to keep up with the variety and quantity of new malware that is being created every day. It is an arms race, and is far from all antivirus programs that are available off the shelf or on the web actually provide a security level close to 100 100%.
Another issue is that viruses and Trojans can alter the software on your computer to make it so that it cannot detect them correctly. This can happen when a virus alters the settings of the antivirus software or when it uses one of its features or functions to create false-positive.
Moreover, there are many instances where the antivirus software does not detect files even though they are dangerous. This happens because the anti-virus has not had the chance to add the particular file to its database yet. To do this, it must analyze the file and analyze its contents with malware-related files already in the database of the antivirus. This is a resource-intensive and lengthy process. And the more slow it is and the less accurate the detection. Besides, the antivirus must install the interceptors of system events within the protected computer kernel to analyse the data before passing it to its engine to be analyzed.