criticism vs judgement

i can't comprehend why some people don't understand the difference between judgment and criticism.

i myself don't like judgmental statements because somehow i feel that they lack the intent of doing good to the person judged. but criticism can be healthy. now take this, three of us were standing near the reception desk when that female went across. she had a new pair of extremely skin hugging trousers on. i mean we all would see her everyday multiple times but today the trousers were not only underlining but also accentuating the hidden talent.

now coming to the point of this post; thus one of us said - what! i never knew she had such lovely piece of a*s [yaar, cmon now i have to censor some words somewhere in my posts sometimes]. the other one quipped, she the new dirty girl of our office. this remark immediately put me off. the other guy was just giving us his critically appreciative comments but this other creep went on to judge the persona of hers based upon his observations. i hate that. although i don't say that i never judge people but i refrain from knowingly judging people.