The only one that can say that is HR. They don’t tell the pilot why they got rejected.

If you don’t ge the invite, you failed the cog or personality test.
if you don’t get the CJO, you failed the HR portion
If you get the CJO, but something flags you in the MMPI or talking with the psychologist, then you get sent to the PARB.
If sent to the PARB, you have to wait for the Yes or No.

Theres no way to tell, why they aren’t getting hired. But more than 70% success rate is awesome.