Leadership. It's squishy.
I've attended countless leadership seminars, workshops, retreats, etc. and read countless books on the topic, and the most intelligent thing I can say at the top is that "it's squishy".
By that, I mean that no matter how hard you try to define, identify or quantify it, you'll just look silly. It's not a math problem or the cure for a disease. It's not a binary condition. You simply know it when you see it.
With that said, some key thoughts on the topic . . .
The more you're willing to be wrong, the better you're going to be at leading.
"Nobody is perfect and you're not going to be the first in recorded history to break the trend."
Define the goal and the parameters by which to achieve it and then turn people loose to get their best work.
"I need a cheesebuger and for it to cost less than $10. I don't need to tell people how to grow the corn to feed the cow that ends up on my plate."
The thing you're responsible for will directly reflect your leadership style.
Take short cuts? So will your staff. Hate all bad news? Nobody will ever tell you any. Until it's too late. If it's good enough for you to do it, they'll do it too.
If the consequence of the risk isn't fatal, be prepared to take it.
The greatness of the result is directly proportional to the amount of risk needed to obtain it.
The only way for your staff to believe in you is to believe in them first.
Trust is always a two way street.
Confidence is contagious.
So is negativity.
So much of what you read and hear about leadership are things that you simply sit back and say "well, duh, I knew that". Well, you're reading and listening because you're not doing. I don't think one great leadership book is really any better than the other, because mostly, it's more down to you needing to be told something the third, fifth or tenth time for you to do something about it. Leadership is hard and does require study to hone it, but mostly it's more about doing what you simply know is right in the face of all the things in the back of your mind telling you "no".