1234avast said:putting block as the behaviour shield option is good.... it doesn't block or deny any legit programs only detects and denies the programs it detects as suspicious events at auto decide... so putting the option to block will block everything recorded down as suspicious events when the option is on auto decide
The main problem with putting it on block, many legitimate processes, software, etc. have suspicious behavior, just because the behavior is suspicious doesn't mean that it is bad.
There is a reason why Avast choose to set it to Auto-decide by default.
Avast developers are not stupid, they know auto-decide is the best option for most situations. Sooner or later having it set to block will corrupt some legitimate processes, software, installers, drivers, etc. It might be awhile before you notice but it will happen.