Underperformers are a drag. You can’t have a great team with an underperformer. But some underperformers are in the wrong role and may not underperform in another role.
Good managers will see potential moves for underperformers that may motivate and improve their performance. The biggest benefit of a move like this is the opening that you can now fill with an elite performer. Move underperformers one way or another to open up gaps that you can fill with impact players.