Why winning IW is a good precursor of USO performance?
Cant help to see how the previous victors of IW managed in the following USO that same year and here's the result
2009 Vera Zvonareva: R64 lost to QFist and future champion, Pennetta
2010 Jelena Jankovic: R16, lost to Kanepi
2011 Caroline Wozniacki: SF, lost to Serena
2012 Victoria Azarenka: F, lost to Serena
2013 Maria Sharapova: DNP
2014 Flavia Pennetta: QF, lost to Serena
2015 Simona Halep: SF, lost to Serena
2016 Victoria Azarenka: KNO(cked up)
2017 Elena Vesnina: R64, lost in 3 sets to eventual finalist, Keys
2018 Naomi Osaka: Winner
2019 Bianca Andreescu: Winner
Somehow these follow up results in USO are quite convincing in retrospective, even considering that Serena was out of the equation during her absent years in IW.
Is it only a coincidence, or something about the court/weather that is correlated between the two results in these two tournaments?
Is there any similar (or even, better) cases?