Whenever it comes to success and business, the best place to start is by committing yourself to not complaining. Of course, it is perfectly fine to raise concerns, to question dubious choices, and to remain thoughtful and analytical at all times.
However, needless and persistent complaining generally accomplishes nothing positive. To the contrary, it drags you down, reflects poorly on you, and can transform otherwise productive co-workers into cynical, whining unproductive co-workers.
In short, focus on solving problems, not complaining that they cannot be solved.