Why are some teachers so rude?

Okay today in our free period I got my planner signed to go to the industrial tech room to finish my project. When I was done with the project I started to walk back to my homeroom and this random teacher I don't was yelling at me and was like "Where are you supposed to be?" And I was like "I just got done with my project and was walking back to my ---" And then he cut me off! And he was repeating the question back to me. I'm like "You can even ask the industrial tech teacher." And he said it again. And I'm think wth so I got so mad. And then he started yelling at me! I mean he didn't even let me explain. Why are some teachers so rude like this? Do you have any teachers or had problems like this?