Offending a co-worker is rude.
Robert's coworker provided Robert with erroneous data so Robert goes to see him to make sure it doesn't happen again.
Robert wants to speak with his coworker.
Robert notifies his coworker about the erroneous data and offers legitimate advice to prevent the issue from happening again.
Robert aggressively talks down to his coworker and characterizes his work as sloppy.
Robert's coworker thanks Robert for informing him about the problem and strives to resolve the issue.
Robert's coworker feels an intense dislike of Robert and avoids him whenever possible.