Are we our own worst enemies while trying to move forward to success?

http://www.inc.com/jeff-haden/5-toxic-beliefs-that-will-ruin-your-chances-for-success.html

Success, happiness, and all the things we think we're entitled to. Nothing is attained without effort, whether physical or mental. I've heard my troops and coworkers express their exasperation...I've even heard, "life's not fair, hurrrumph!" from a grown man. Eliminating toxic thoughts and self doubt is the cornerstone to success.