because some times spyware make computer nonfunctional.
Paul Weinstock
https://theworld3rd.com/forum

Hello Paul:

ClamWin detects quite a bit of spyware. During the last couple of years, the the AV firms have started to realize that they need to detect ALL malware--not just viruses, and most AVs now detect a lot of "high profile" spyware at least. Clam's detection rate against spyware was 92.8% in Virus Bulletin's last test--see https://www.virusbtn.com/news/2008/09_02 on the web. That was a couple of points better than its virus detection rate! Both of Clam's detection rates were better than that of some high profile commercial AV products.

An up-to-date dedicated antispyware/antimalware program will still detect more spyware than a dedicated antivirus program, however. For one thing, the AVs don't bother with a lot of spyware "traces"--they just concentrate upon the primary spyware payload and don't do anything with the logs and registry entries dropped on a machine by the spyware. Many AVs consider these traces to be harmless after the payload is detected/removed.

To a great extent, an antivirus program is also dependent upon its users to provide it with samples of undetected malware. For instance, Clam's core user base is Linux-based email providers and in-house email servers. Consequently, a majority of malware samples received by Clam is stuff distributed through email to Linux servers. That is why we need more ClamWin users--so we can provide Clam with undetected malware from average users, which will consist of more Web-based malware. That alone will increase Clam/ClamWin's detection rate.

Regards.