2009-10 Cavs winning %: .744
2010-11 Cavs winning %: .232
2009-10 Heat winning %:.573
2010-11 Heat winning %:.707
2013-14 Heat winning %:.659
2014-15 Heat winning %:.451
2013-14 Cavs winning %:.402
2014-15 Cavs winning %:.646
Remember though: It's not that simple. This wasn't just because of LeBron. There were all kinds of different factors. The 2010-11 Cavs were a COMPLETELY different team. In addition to LeBron, they also lost a 35 year-old Zydrunas Ilgauskas and Delonte West. The 2018-19 Cavs are a COMPLETELY differen team: They lost Jeff Green and Jose Calderon.
Sure, it just happens to be that each of the three times LeBron left, his team from the previous season became significantly worse and the team he went to became significantly better, but is it really that hard to believe that this is nothing more than a coincidence, 3 straight times? I mean, there are people in the world who have won the lottery more than 3 times.