to be honest, i think alot of it comes from the fact that Jennifer and Steven have been there.....Paula was always the nicest judge when she was there, and she was the only one who was a star singer....they know what its like to get rejected, and you can tell someone they arent good enough, without chastising them, and embarassing them....simon wasnt a performer (he was a great judge of talent) but he hadnt been the one on stage, so he was more harsh, so was Kara......Jennifer and steven have been through it all and can judge without just reaming a person...
I think thats alot of it......