No, it's just a thing they tell themselves to hype themselves up and avoid the depressing truth most teams face, "we're far from the best and probably never will be the best, and there's a good chance we're going to lose this game".
Well, in work the depressing truth is "my boss is my boss, I have to do what they says so I can eat". A little chant to remind yourself that work should, ideally, be mutually beneficial and based on mutual respect, and that you're not a slave to the company and its politics is all this is.
One thing that distinguishes a professional is the focus of what they work on. If somebody tells you what to do, and it’s not in that narrow range, you are not a professional anymore; you’re a stand-in for a professional, and you’ll get treated poorly.
This is the most important one to me - I do my job for exactly that reason - it is a job. A business transaction where I get a specific amount of money in exchange for putting time and energy towards their goals. It is amazing how much you can accomplish while not letting the BS get to you once you take the attitude of your work being a daily business transaction.