It's bad to do something that is your co-worker's responsibility.
Jeff has a new colleague who doesn't have a lot of experience and works slowly.
Jeff wants to help his coworker finish his work before the end of the day.
Jeff has a meeting with his coworker during which he gives him helpful pointers about how to complete tasks quickly.
Jeff decides to finalize one of his coworker's projects.
Jeff's coworker completes all his tasks efficiently and is proud of himself.
Jeff's coworker feels disenfranchised and underestimated.