Haha, I'm no expert lolol. But another theory is that some personalities repel each other. It has more to do with Socionics, so I don't understand it fully. But basically, types with the same functions as you in reversed order are called your 'duals', while other types are called your 'conflictors'. For myself, I think ESFJs are my duals and ESFPs are my conflictors. ESTPs are sopossed to be the 'duals' of INFJs I believe..