Briefly describe your previous jobs

Unfortunately, people cannot read your mind. Which is why it's important to write a brief description of your previous jobs. If you're too busy, then write just ONE sentence. Example: "I was responsible for (doing such and such)."

Just listing your previous positions without descriing them, sends a very negative impression. People might think you're the kind of person who doesn't focus on details and doesn't execute tasks properly.

Better not write anything than write something that shows unprofessionalism or an I-don't-care attitude.