Why do we all have diffrent voices?

Its very rare to say that somebody sounds like someonelse.
Why do we all have diffrent voices?
We are all made different. No one%26#039;s the same.
Why do we all have diffrent voices?
to be remembered..to leave a trademark..
Reply:If we all sounded the same there would be confusion. You would hear a voice behind you that sounds like your aunt, your brother, your milkman, your math teacher, your dentist, your nosy neighbor, your father,etc.