Why. Novak was the player of the year in 2013 even though he was not YE #1, since Nadal won too many MM clay tournaments.
That was different,
Novak won ITF Player of the Year
Nadal won ATP Player of the Year as he finished YE1
Serena won WTA layer of the Year as she finished YE1
I don't think you can win the ATP or WTA unless you finish YE1.
The ITF Players of 2014 has not be released for either Male or Female..
Serena has not won 6 straight ITF,
2008 Jelena Janković
2009 Serena Williams
2010 Caroline Wozniacki
2011 Petra Kvitová
2012 Serena Williams
2013 Serena Williams
The ITF Player of the Year is meant to represent the best player of the year, and weights Majors highly and compares H2H Masters. The aim is to identify the Best Player of the year.
The ATP Player of the Year is meant to represent the current players chances to progress through a tournament, hence, it's for seeding purposes and rates Masters, 500, 250, etc. It does not represent the best player rather a players ability to progress through tournaments with some weighting on their relative importance.
Generally ATP = ITF especially since the 90's.
So the comment
Of course it has to be the world no.1!
is correct for the ATP & WTA rating. And therefore the whole award is just a advertising or celebratory event for ATP or WTA to thank the player for making them money.
PS The ITF woman's PoY seems to be a real mess.