I'm almost going to start my PhD. Out of curiosity, I searched for several effective researchers in several fields over the internet. Most of the common property among almost of them are
1) Working under the supervision of another effective researcher.
2) Not doing PhD in my country.
The second rule fails if and only if his/her supervisor satisfies both rules.
I considered some other factors such as time of spending, passion on the subject. Although many people I saw in my colleagues, friends, seniors etc., have these qualities are not as successful as the people who have the above two points (country, supervisor).
In this context, even I have so much aspiration, the two factors are pushing me back due to this empirical evidence.
Thus, my question is, whether the country and the standard of the supervisor affects my PhD quality and hence my career?
Note: I was neither a child prodigy nor an exceptional person but an average student. Hence please answer realistically.