Well...I don't know
I feel as soona s public voting is brought in,many additional factors are brought in to bring up TRPS etc. But I also think that sometimes the best can win like anamika,sanchita n aishwarya of chote ustaad(though anwesha was better,aishwarya was also good)
But yes,in the adult shows we may have problms with the winner more often. amant n Nihira were def. winner material, even Amit Sana was beter in Indian idol 1, AMey date in Indian idol 2, Deepali in idl 3, Ritisha in VOI2, Abhas in VOI1, Shashi in challenge 2009. But theya re my favourites for their singing n not vice-versa.
Hope the best wins every time,and usually even a layman can say who's the best. But public may get influenced by othe factors like region, drama, performance etc.
Why else did Ankita Mishra get more votes than deepali? Why did Tanmay get more votes than Rohit Shyam rao/aamir hafez? Why did Ishmeet get more votes than Abhas? Why did Yashita get more votes than Pratibha?