Antivirus is a popular product that has been advertised as a common commodity similar to a toothbrush, detergent or car. The popularity of antiviruses isn’t the only reason they’re popular have flaws.
It is simply not possible for antivirus programs to keep up with the volume and variety of new malware that is becoming developed each day. It’s an arms race, and not every antivirus program available on the market or available online can provide security that is nearly 100%.
Another issue is that viruses and Trojans are able to alter the software running on your computer to make it so that it is unable to detect them correctly. This can happen when a virus alters the settings of the antivirus software or when it exploits one of its features or functions to create a false-positive.
In addition, there are many instances where the antivirus program does not recognize files even if they are clearly dangerous. This is because the antivirus has not had the chance to add the particular file to its database yet. In order to do this it must analyse the new file and compare its content with known malware-related files in the antivirus’s database. This is a long and resource-intensive process. The slower it runs, the less accurate is the detection. The antivirus must also install interceptors that study system events deep within the protected computer kernel in order to send the data to its engine.