In the 21st Century marketplace, blaming the "office girl" is as dumb and outdated as a schoolgirl taking up smoking.
Out house-hunting last Saturday morning, Justin and I waited outside a vacant home for the agent to show up. 10 minutes later, Justin called said agent, only to be told, "Yeah sorry, it went under contract last night. Damn! The office girl was supposed to change the details on the internet. She stuffed up. Anyway, I have another one in a different area you might be interested in."
"No thanks. This is the one we're interested in." Justin hung up, turned to me and muttered, "Bloody liar. Reckons his office girl didn't change it. He forgot."
Lying or not, blaming a subordinate will cost you credibility both as a salesperson and a leader. It's weak and it makes your company look weak (let alone using the phrase "office girl"). Even if he was telling the truth, it looks like he's lying. When it's your sale, it's your responsibility.
If he'd said, "I'm so sorry, it just went under contract late last night and I should have made sure the open was updated," we would have accepted these things happen. (Though when Justin and I were in real estate sales, we would have shown up for the open anyway because contracts can fall over.)
Resilience is the ability to come back from a setback. Resilient people take ownership of a mistake. Doing so is risky; someone might get mad at you, you might lose a sale. However, most people will appreciate your honesty and are more likely to trust what you say you will do to fix it. How well you follow through may even win you a loyal advocate!
Even if it was a staff member who made a mistake, if it's your face and your name out there, the responsibility still lies with you.