Once again, too many excuses.
There is something called career progression.
Petra makes top 50 and wins 1st WTA tournament at age 18.
Petra made 2010 Wimby semi-final, makes top 30, at age 20.
Petra wins 2011 Wimby, ends year at number 2, and wins 6 tournaments at age 21.
Petra makes slam semi's 2X, quarter 1X, and 4th rd 1X, wins two tournaments at age 22.
In 2012 (still at age 22), not so well, not so much.
The progression has halted, even against worst opponents.
Petra's level of play and consistency, is now comparable to her 2010 levels, hopefully not worse.
That's the problem. At least at the moment, she's in a decline.