Omar Asali isn't keen on hiring smooth talkers.

Workers who are too self-promotional and careful to say the "right words" usually look out for themselves, rather than their organization or the people around them — a red flag in the recruitment process, says Asali, 53, the CEO of eco-focused packaging company Ranpak.

"You always have to be careful with people that are very smooth talkers and very promotional," says Asali, who's been running Ranpak — which has a market value of $661.06 million, as of Monday afternoon — since 2019. "I'm not hiring people because their presentation skills are phenomenal. I'm hiring them typically because I need certain tasks and certain jobs done."

At such a large company, Asali isn't always involved in every single hiring decision. But when he hires "very senior executives," he makes a point of discussing both work-related and non-work related topics with candidates. The better he gets to know them, the more easily he can identify whether they're "doers" or "talkers," he says.

"I am not the type of person who will recruit because I've done one, two or three rounds," says Asali. "We will do meals, we will talk about social things — really try to understand these people and their background before I bring them over."

At the interviewing table, Asali often gives candidates a prompt that he calls "very insightful": Tell me 10 words that immediately come to mind that describe who you are. Most people respond quickly, and their off-the-cuff answers can illuminate aspects of their professional and social personality more effectively than anything they've prepared in advance for the interview, he says.

"The more honest they came across — the more sincere they came across — the more I enjoyed the conversation," says Asali. "You would be surprised with people I hired that were pretty open and vulnerable about things about themselves."

Asali isn't the only interviewer who asks questions that probe at people's self-awareness and ego control.

Kickstarter CEO Everette Taylor, for example, asks candidates to discuss a time they made a mistake or failed. People who recognize and take accountability for their shortcomings in their answer demonstrate a strong ability to work with others, he told CNBC Make It in August, whereas those lacking self-awareness "really struggle" with the prompt.

But few people, if any, are perfectly self-aware — which is why Taylor himself constantly works to get a better sense of his own strengths and weaknesses.

"I try to keep my ego at the door. I'm wrong all the time. I have an incredible team that's super smart and will put me in my place, and I love that," he said.

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