If else statement bash script

I'm not sure why my script is always executing the last statment else even if the files file1 and file2 are not empty :

if [[ -s $file1 && -s $file2 ]]
 then
    echo "files are good"  

elif [[ -s $file1 ]]
 then
    echo -e "$TEXT2" | mail -s "$SUBJECT" "$RECEIVER" &>/dev/null

elif [[ -s $file2 ]]
then
    echo -e "$TEXT1" | mail -s "$SUBJECT" "$RECEIVER"  &>/dev/null

else
    echo -e "$TEXT3" | mail -s "$SUBJECT" "$RECEIVER"  &>/dev/null

fi

The requirement is to send a notification if one or both files are empty