His tardiness.

"I want to talk to you about your tardiness, John," she said firmly.

"But I've only been late this one time."

She stood up and walked over to him. "I know, but we don't want to make this a habit, now, do we? I think we need to nip this in the bud."

He sat there, not understanding what she was saying. "What do you mean?"

"Do you prefer the carrot or the stick approach? I mean, would you rather I write you up or should I give you a positive incentive?"