The answer is just a four-letter word.

I was talking to a colleague of mine about a previous manager that she had and she said "he is one of best managers that I've worked under".

Because I want to be the best manager that I could possibly be, I asked her about what made him a good one.
Her reply was pretty simple, she said and I quote,
"oh he cares about everything, he cares about people, technology, our personal development and moving the organisation forward."

At that point, a light bulb went off in my head. To be a good manager, you don't need to have the answer to every question, nor do you need to be an expert in a particular field. You just need to care. You need to care about the right things, you need to show that you care too, and you need to help and encourage people to achieve more than what they thought possible.

So there you have it, a four-letter word answer to one of the most frequently asked HR questions. CARE.