For a Project Manager human beings do not exists on this planet, rather what they see are dogs. Every stakeholder is ready to take a bite of your flesh, until and unless they are satisfied that they have eaten enough meat and drank enough blood to their satisfaction. And since you see everyone as a dog, you always get treatment like dogs. Wait, sit, drink and go are normal instructions that they have to follow. Don't take stress if you are new project manager, you will soon be accustomed to these traditions.
Therefore as a project manager, your first priority should be PROTECTION. How to protect yourself from external and internal blows? Get things done at the right time. A project manager is always caught if he has not done his homework before the meeting. He needs to understand the audience, and then be prepared on what is going to come to him, and what should be the answers. A lazy project manager is therefore a doggy project manager. He himself is inviting people to treat him like one! Self-protection is one aspect, second is to protect your team. And the second aspect is more dangerous. Because if the customer bites your team member; than the rest of the members, technical lead, CTO and customer will get a good taste of your flesh.
Second and most important, is to understand the requirements of your boss's boss. The message that comes through hierarchy has least reach-ability. And this is common in organizations. So every time you get exposed to management, you start giving a look of a monkey trying to only grab couple of bananas, out of the bunch hanging on the tree. So be smart and play smart. Your CEO is also a monkey; it is just that he wants to see many bananas on the table. The more the bananas the bigger the dollar sign in your CEO eyes, and better you are as a project manager
And then who forgets documentation? You are right, only the doggy project manager forgets to document the commitments. So if you want to live a life of a lion, then document critical decisions during project execution. Humans; be it in business or professional services; are biggest liars. And they would never want to let go any chance to manipulate.
Lastly it is the personal life of project managers. Due to their intense experience on the field, they gradually become skilled liars. They normally put lags, and use delay tactics in their personal life. They know how to manage expectations in some way or the other, so the personal life of project manager is normally balanced, and far better than their technical counterparts.