can u guess a typical password?

i heard my colleague talking about company email account.. they was talking about sending & reciving email from a client..
( A ) say just asks them to sent/email over the CAD drawing to ( B ) email.. than ( B ) say he won't be here to revice the email as he'll be out later.. ( A ) say he'll just open ( B ) email~lah.. ( B ) replied saying u know the password ~meh.. ( A ) say oh its all the same~lah *0123*
( note: its the password given when u been given the new email account.. )
( B ) *speechless*