Don't tell me, show me.
We have all heard the excuses and disagreements about the reasons why someone has performed poorly or made a mistake. All the apologies and plans in the world lose credibility without the intended results becoming a reality. Time will tell if someone is properly motivated and actually has the ability to change. Time will also tell if someone may be in the wrong position on the team. Consistently poor performance and repeat mistakes may be an indicator that a seat change or transition is necessary.