they have a bad history on adding an important/dangerous malware in their database which was one of the most recognized malwares in its time .. it was belong to a country for spying another country... ( i cannot be clear here ... i'm sure you underestand

) some of companies wont add it in their database till that malware did its job... one of those company was Avira , another one was Symantec... this is wat hurt my trust to Avira & Symantec
by the way excuse me for my not real good English, i'm not an English speaker