I judge people by their behaviour. For example, I absolutely
loathe a certain group of students in my class because they would
not stop talking and horsing around. I wonder what they are there
for. They are disruptive and inconsiderate. I don't see anything
good in them and I think they are good-for-nothings.
Honestly though, I don't know them personally and that assessment
is going to come across as judgemental and biased. But that's all I
see of them from their behaviour.
I don't like them, and probably never will.