You brought a bad attitude to each job and expected, as evidenced by your post here, that the boss somehow owes you something, he doesn't.
If, in your first example, your boss didn't think it was time to offer you a permanent position at that time, that was his right. Maybe he thought you grew a lot as an employee during that next 2 months and felt more secure offering you the job, who knows, but it was not your schedule that was important, but rather his, it was his company.
I hope you have better luck with your employees than your bosses had with you.
By the way, respect is earned, in case you did not know that.