Is it really essential to master reset and internal drive format after FW upgrade?

Posted by shuvo13
Yes i know before firmware upgrade it is needed to do a internal drive format and a master reset. As this could make any problem during upgrade. But after upgrade why it is need to do master reset and internal drive format? as the upgrade was successful and we did it before upgrade i dont think it is needed. Do some of u guys tried not doing that things after upgrade? did someone get any problems? then why it is recommended? I mean we dont do a internel drice format and a master reset after buying a new set thought a brand new set is already undermaster reset done. So why here? any logic?