Well the problem as I see it is who decides what is a trusted site and what is the criteria to become a trusted site.
We have seen lots of sites being blocked in the past and not all of them are small sites. Some very large sites have been blocked at times, I think even google, yahoo and youtube, etc. Now if they are getting blocked/alerted on, it must mean they aren’t on the list, which would be strange.
We didn’t get an clear answer from Avast about that either.
But in my personal opinion Avast ( Web ) Shield settings should be set by default to protect you.
And performance settings should be optional.
The option “Warn when downloading files with poor reputation” is not selected by default, and it is recommended to select it.
But I think that is common knowledge ( but maybe I am wrong ).
It has two sides to it. It will ofcourse warn when downloading files with poor reputation but sometimes it will flag legitimate programs such as Windows Update so is disabled by default.
There is certainly a case for both options:
Having a poor reputation doesn’t necessarily mean it is malicious or the web shield would be throwing up a different alert.
Who defines what the bad reputation is.
And finally as Alikhan mentioned, user experience; whilst this wouldn’t unduly concern an experienced user, but might spook an inexperienced user (probably a majority of avast users).