Serial entrepreneur David Royce has been building companies for years. Royce founded or co-founded three companies in the pest control industry beginning in 2008, and owned a company in the industry before that. He is now on sabbatical as he figures out his next career move.

In his decades building businesses, Royce has identified some immediate red flags when interviewing job candidates. One is negative talk about former employers. "It's totally okay to have both positive and negative things" to say about them, he says. But if a candidate focuses mostly on the negative, "then the problem is likely" that person.

As such, Royce has a question he likes to ask people he's interviewing to suss out their disposition.

'How might you have changed that situation?'

During the interview, Royce asks prospective employees to "tell me about your previous employer," he says. "What are some things that they could do to improve?"

Then he pays attention to how they respond. Did they struggle with morale? Did they feel like they didn't have enough autonomy? For any pitfalls they mention, he asks, "how might you have changed that situation?"

Ultimately, "it's just about hearing solutions," he says.

"Are they constructive in the way they critique," giving examples of how they would've or could've solved the problem, or do they "just want to complain about it?" If the latter is the case, they would likely bring that negativity into Royce's company with them, he says.

'The No. 1 thing that makes A players want to leave is B players'

One of the problems with having this kind of personality on your team is not just that they aren't looking for ways to move forward but that they can also drag down the morale of the whole team.

"The No. 1 thing that makes A players want to leave is B players and certainly C players," he says. People who aren't focused on producing and creating a positive environment can "spoil your culture and then potentially force out the best talent."

When choosing who to hire, "I want to make sure somebody is generally positive and looking for opportunities to or ways to improve," he says.

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