If you've ever hired someone before, you've probably Googled "what to ask in an interview," or perhaps relied on questions you remember from your past. 

Problem is, the all-too-common questions aren't always the right ones. 

Especially in a small business or startup environment, where jobs are constantly shifting and the scope of work is expanding at all times, questions shouldn't be primarily focused on what candidates have done before. Instead, interviewers should focus on one thing that won't change: who the candidate is as a person.

In short, to find the right fit, you need to figure out how challenged and fulfilled someone will be with the problems and work that they'll be doing.

It's notoriously hard to get to know someone in one interview, and it's even harder when the interviewee responds with what they think you want to hear. It's also rare for candidates to have the self-awareness and confidence needed to be honest about whether or not the role is truly a good fit

So, what can you do to ensure that you're making the best hiring decisions? Here are four critical questions that you should start asking in every interview:

Question 1: What's the thinking or problem solving that you're best at?

Why you should ask it: You'll learn what keeps this person challenged intellectually. And this is important: If you want your team to be hungry, energized, and motivated to take your business to the next level, they need to be challenged in the right way. The only way you can ensure that they are is if they can tell you. Knowing the answer to this question will make it easy to see if they're the right fit for the work that you'll need them to do.

Question 2: What's the impact in the world or on others that provides you with fulfillment?

Why you should ask it: Everyone wants their people to jump out of bed and run to work. What creates this kind of never-ending energy? The answer is intrinsic motivation, the type of motivation that comes from within and can't be bought with gifts, perks, or money. It comes from someone feeling connected to the impact they're making on others and in the world.

If someone can tell you what provides meaning for them, you'll know immediately if that impact if feasible in this role or not. If they're a superstar, they'll be able to tell you how they can apply their Purpose to your open role or to your business. And that's exactly what you want. If you have intrinsically motivated people, you have a team that is unstoppable.

Question 3: Do you see this role as a good fit for who you are and what you need in order to be engaged?

Why you should ask it: This crucial question allows the individual to tell you why or why not the open role is right for them. When someone's clear that this is the job for them, they should be able to tell you why with an enthusiastic and detailed response. Listen for self-awareness, honesty, and confidence, as well as whether they can identify how they will be challenged intellectually and fulfilled by the opportunity. If they can articulate these elements, you've likely got a great fit.

Question 4: What are your values, and what kind of culture is a great fit for you?

Why you should ask it: This question allows a candidate to pull back the curtain on how they behave at work. Also, assuming they've done their homework (and you make these aspects of your company public), they've researched your business and have a sense of your values and cultural norms.

They should then be able to discuss how their personal values fit in with the company's. You should, of course, seek to hire people from all kinds of backgrounds and look for those who think differently from you, but it's important that, at the core, everyone shares similar values. This is what makes a great culture fit. 

If you use these four questions, you can walk away from an interview knowing if someone's self-aware, if they'll be truly challenged and fulfilled, and if they'll fit in with the culture of your company. If you have those nailed down, you're bound to make a great hire.