We all know what kind of difference a good teacher can make in someone's life. A skilled educator has an opportunity to inspire students to pursue their goals and talents, can recognize their strengths and give them the most important knowledge they can offer. While we all should celebrate all of the amazing teachers out there, many schools still lack compassionate, thoughtful and talented teachers. A Twitter user who recently started a thread asking people to share their crappy teacher stories proves that some people are simply unsuited to do this important job. In the eye-opening and shocking thread, people shared stories of harrowing teachers who abused their power over students, humiliated and bullied them.