I acted like a complete jerk to my students just to prove a point

Article in The Conversation:

Not every bad thing that an instructor does is as bad as the ones I did for our study. Some are relatively minor, such as showing up a few minutes late to office hours. These types of things may detract from a learning environment, but students can recover easily from a few simple mistakes or inconveniences caused by a professor.

But some types of serious misbehavior can hurt the learning environment. These include taking four weeks to return graded assignments, not responding to student emails, deviating substantially from a syllabus or showing up ill-prepared.

The worst thing an instructor can do, from my perspective, is antagonize their students. It may be rare, but students regularly identify antagonism as the most significant misbehavior.