I am writing to apologize for my unproductive efforts during the [project/task]. I understand how much of a disappointment this must have been for you and the rest of the team, and I want to express my sincerest apologies for letting you down.
I know that I had been assigned a significant role in the project, and I recognize that I failed to deliver on my promise to contribute in a meaningful way. I regret that I was not able to provide the level of support and commitment that you and the team had expected from me.
The truth is that I had taken on more than I could handle at the time. I was juggling multiple tasks and responsibilities, and I was not able to give my full attention to the project. I understand that this was not an excuse for my lack of performance, but I wanted to explain the circumstances that led to my failure.
I am deeply sorry for not being able to meet the expectations that you and the team had for me. I understand that this was a major setback for the project, and I want to assure you that I am taking steps to ensure that this does not happen again.
I am committed to making up for my mistakes and I am willing to do whatever it takes to make sure that I am able to deliver on my promises in the future. I am confident that I can make a positive contribution to the project and I am determined to prove that I can be a reliable and dependable team member.
Once again, I apologize for my unproductive efforts and I hope that you can accept my apology.