explanation on combos?

From what i heard you sqli a random site get the emails and passwords db and the insert it to egg.crack.
so youre supposed to hope the same email is registered on mc?
also what is currently the best, fastest method for cracking - is there a new 2015 method?

well the combos i sell are In fact From hacked websites but i get nice hits on origin

bruh, add me on skype