Trustworthy people distinguish errors from excuses.

There is a difference between an account of what went wrong and a case for why it was not your fault. The first names the decision, the missed check, the thing you did not do. The second is technically accurate and reliably leaves the listener less informed. People can tell which one they are getting almost immediately.

When explaining a failure, put your own part first and the circumstances second, if at all. Say what you would do differently. The circumstances usually speak for themselves and land better when you were not the one arguing for them.