When hiring, I focus on different things depending on the role and the candidates.
If it is a entry level role, I mostly ask situational behavior questions - I am trying to understand if the candidate would be a good fit for the organization and the demands of the role. I don't spend a lot of time on the knowledge, skills or work experience as normally I hire recent graduates from a university (assumption being they have basic engineering knowledge), should have minimal work experience and we will provide significant on the job training to close any knowledge gaps.
if it is a senior role, in addition to situational behavior I like to see 2 other things: depth of knowledge in the subject matter and professional growth (knowledge/training).
Also when hiring leaders (managers), I tend to focus more on ability / skills to see the overall business picture. Candidate should ask me many questions about the products, the people, the processes, partnerships, programs, and more.
Always be respectful, have empathy for the candidate, create a relaxed and dynamic conversation and be clear on what you are looking for.
I like the two previous answers but I have been recruiting for 24 years and that is my job so I saw a different question than perhaps they did.
I would say, you could hire me as that is what I do - just kidding. To start hiring people, it depends on many factors, but I would ask yourself a few things.....How many folks you want to hire, what their skill sets need to be and where would I find folks with that skill set.
You could ask friends and get referrals. You could use a service like www.ziprecruiter.com or www.Indeed.com or www.Monster.com or if it is just for like a painter, you can go put adds up at the grocery store. I guess, I would need to know what types of people you are are looking to hire and then I could answer better. For par-time folks or contractors, you could uses a site like www.bark.com or www.flex.com or www.houzz.com etc.
I am not sure I fully understand your question. Usually companies start hiring people to be able to have a bigger workforce so have more things done while still having the proper budget to pay the persons.
If you're asking what is a good level to get hired by a company, I believe Rudy has a good answer. Less and less companies are looking at the best candidate that has all the knowledge. We assume you have the basic knowledge for the job you apply for. The rest will come with experience. What we do want to make sure is you are a good fit for the company and the team. Therefore, we focus a lot in trying to know you, your reactions in fake or real situations. We are looking to see if you are able to learn from your mistakes, to see if you are curious. That will fill the gap of anything you do not know out of school (and there are lot of things schools do not teach you).
Of course, the higher the job position, the more we ask. I expect a senior position to have a certain level of knowledge in the domain this person is applying for the job.
One thing in addition to the obvious "be honest" is be yourself. I do not like interviewing 16 candidates that all do the same things. I am not hiring robots but team members with whom I am going to spend 40 hours a week, even more. Show who you are, what you as the unique You can bring to the company. Be proud of what you are, what you think. Be also critic about yourself but be sure enough that if you get challenged on a question, you can defend your point of view. Being young does not mean being wrong. A new pair of eyes, a new way of thinking is what makes humanity moving forward. But do not be stubborn if you see that you are wrong.
And unfortunately, every company has its own style so you will have to adapt.
Personally, when I interview young graduate for their first time job or student for interns, I challenge them as hard as I can so they feel cornered. This is usually when I get the best of them. How they accept the critic, how they learn from the wrong answer they gave me and so on. Over an one-hour interview, I may spend only 10 minutes on a technical exercise. The other part is simply just questions and challenge on the candidate's projects that the candidate decided to speak about.
I hope that helps.