When have you misunderstood instructions at your last job? What was the consequences and how did you overcome that?

Think of a recent example of a time when you made a mistake at work. Did you own up to it? How did you fix it? What was your overall behaviour around the error?

IE: "Last summer I was working for a private client and they requested some new trees be planted. I added too much mulch around them and ended up suffocating a few of the new trees. My client called me with their dissatisfaction and I immediately apologized for the error. I was able to resuscitate all but two, which I replaced using my own funds. It's a mistake I will never make again."