How did the image of Private Quelch as a 'hero' gradually change into a 'villain' in the eyes of other trainees?

the-man-who-knew-too

#1

How did the image of Private Quelch as a ‘hero’ gradually change into a ‘villain’ in the eyes of other trainees?
or
Why did certain respect towards the Professor gradually change/develop into terror among his colleagues and what kind of treatment did Private Quelch get?


#2

Initially, everyone was very much impressed by Quelch’s excessive knowledge and his witty remarks. But as the days went on, this habit of the Professor was disliked by others. Moreover, he corrected the mistakes of his colleagues publicly, which embarrassed them and as a result, they gradually started to develop sheer terror of the Professor. They got sick of him and hit back at him with practical jokes.