Runs But Can Never Flee

Riddle: It runs and runs but can never flee. It is often watched, yet never sees. When long it brings boredom, When short it brings fear. What is it?

Answer: Time, which is often watched when you stare at a clock. Source: https://www.riddles.com/index.php/527

It runs and runs but can never flee. It is often watched, yet never sees. When long it brings boredom, When short it brings fear.
What is it? — Runs but can never flee by Anonymous Riddle