wulke

This was also true in the military:

At basic training, our drill instructors often said that recruits with no experience shooting weapons were easier to train than other recruits who had experience because it was much easier to teach best practices to someone who was a "blank slate" than it was to retrain best practices to someone who learned improper methods.

I haven't exactly seen this idea like-for-like in the "corporate" world, but I believe the general premise is accurate.