Every hiring mistake I have made came from the same place. Someone had the experience, sounded the part, and I let that stand in for the thing I actually needed. The thing I needed was a reason to show up on the bad days.
Why skill is the cheaper one
Skill has a curriculum. A pitch, a set of objections, a debrief rhythm, ninety days of reps. I can teach it, and I have taught it to people who had never sold anything. Hunger does not have a curriculum. It is either there when they walk in or it is not, and no amount of coaching installs it.
What hunger looks like
It is not intensity. Loud people are not necessarily hungry, and quiet people often are. Hunger is a specific thing the person wants that this seat can get them, plus evidence they have already done hard things to get closer to it. Both halves. A goal with no evidence is a wish. Evidence with no goal is a resume.
The question
Tell me about something you wanted badly enough to be bad at it for a while. Then be quiet. The hungry ones have an answer instantly, and it is specific, and there is a moment in it where they almost quit and did not. The others reach for a story about a job.
Then build the gate
An interview is a guess. The first two weeks are the proof. Make the training something you have to pass, not something you sit through, and watch who treats the gate as an obstacle and who treats it as the point. The hire is the second one.
You can train almost anyone to sell. You cannot train anyone to want it. Interview for the second thing and teach the first.