Dhuuso, There are actually more than 12 islamic sects or/and had been or will be(some of them who didn't appear yet will appear possiply), Islam will generate more sects than christianity and Judaism each in their separate way generated. Just because there are sects, it doesn't mean islam in itself is a devided religion that accepts devisions. Islam is one, will remain one, but some muslims introduced into their daily rituals and will introduce into their practices and beliefs what wasn't taught by the prophet and never had been practiced by his companions. Whatever someone presents as islam, it has to be found in the Quran and in the Sunnah. If people were allowed to form their own versions of islamic religion, such directive would have been given and people would have been told to worship god as they see fit under islam.
Now, who doesn't consider before he replies Mr.Dhuuso? You picked on me because you thought I was an easy victim for you this morning? Well saxib, like I said before, it is waste of time explaining things to people like you. I would rather kid around and waste my time on useless things than reply to an ignorant person who thinks he understands something when he doesn't. Be sincere and you shall find someone who will be willing to lend you a hand in discovering what you have lost.
PS: Don't make your reply lengthy as usual writing maalaa yacni fara badan. A two liner slam dunk from you will be fine to send me back crawling to bed

I am waiting macallinka ee la soo bood warkaada.
PSS: Refer to Viking's replies in shia discussions. It can be useful.