Arcticsid installed one antivirus program on a new PC that already had another. He asked the Antivirus & Security Software forum if that was a good idea. The term antivirus has come to mean a program that launches when you boot your PC and stays running in memory. Every program running uses RAM and clock cycles, potentially slowing down every other running program. The two programs may conflict with each other–remember that every time you download a file, both will try to scan it.”]
Source: https://www.csoonline.com/article/2133326/one-antivirus-program-is-better-than-two.html