why does this keep happening?
 

i went to change my o2 sensor yesterday and the threads in the o2 bung came out with the sensor? i had anit seize on it when i installed it wtf
this is the second time this happened? any ideas?

I've never had that happen, and don't recall it happening to anyone else. If this happened before, what are the chances they installed the wrong bung/thread pitch? That you cross-threaded the O2? Used the wrong grade of goop?

slim to none the sensor was a ac unit and me being a machinist its easy to tell when the your cross threads and not

and seeing as this happened upon removal idk
its a PITA