Why Kakashi doesn't have a rinnegan? He got a little Uchiha blood from Obito and he has some Senju blood,so why doesn't he have a rinnegan ???
Yeah there is a tonne of factors you are missing in your question: Plus calling the thread maker retarded is not necessary, he may just be asking for some information to be informed on the matter.
1) kakashi does not have senju DNA
2) Kakashi only has one Sharingan Eye
3) Kakashi does not have the Chakra reverse to even support rinnegan
4) Kakashi does not have Uchiha DNA either, he just simply has the eye
It is just impossible for kakashi to get rinnegan, unless the eye's are implanted or Obito might release it in his Sharingan eye, because i believe that there Kakashi and Obito's sharingan eye's are connection(just speculation thought)