Delivering effective feedback requires the right mindset.
Basically, effective feedback (positive or negative) makes the person even more motivated to do it even better next time.
Feedback ties into the psychology concept of operant conditioning.
With positive feedback, you using positive reinforcement and ADDING (positive) something GOOD to increase the behavior. Basically—praise. Properly delivered praise works really well! The person feels good about their work, and they feel good about you.
If you are criticizing, you are using positive punishment and ADDING (this is the “positive” part, not the tone) something BAD to decrease the behavior. This often doesn’t work—the person feels bad about what they did, but they might also decide they don’t like you too much, either. Improperly delivered negative feedback kills motivation, kills morale, and diminishes people’s perceptions of your leadership skills. It’s one of the main reasons people cite in their exit interviews. Poorly delivered feedback causes retention problems.
When someone does something wrong, don’t just “red pen” it. Don’t scream in their face like a drill sergeant in an old movie. Figure out WHY they made the error, then fix that. Do they not know how to do it right? Give them training. Do they not know what the final version is supposed to look like? Provide a template or an example of a previous product. Are they unmotivated to do it well? Remotivate them so that they see the value in their contribution. Basically, frame your feedback to vector them to success, not to punish them. Ideally, don’t take the work back—leave it as their responsibility, but make sure you give them the tools to do it well.