Depending on what you use your computer for, this may be an important concern. Free antivirus options are easy to install and use, but are very limited in their flexibility. They come as-is, meaning you can’t pick and choose what it monitors or how it reacts. For example, users occasionally find it necessary to disable ALL protections in order to install a network game. Paid versions are more likely to allow you to adapt the way it runs, switching features on and off as required.