After having observed various colleagues, clients and friends over the last 10+ years and watching how some of them have evolved, I realised some common traits in those who consistently fail to deliver in their personal and professional lives.
Ego. People like to hear what they want to hear - most people don't like to be disagreed with. They like to hear the good things about them, and that their opinions are important and resonated by everyone. Very few will appreciate critical feedback even though what they are doing may be wrong. Remember this also the next time someone steps on your ego.
Laziness or sloth. Taking for granted that someone else will do your work. This usually comes with the feeling of a sense of entitlement due to one's age, experience or perceived wisdom.
Inertia. Knowing what needs to be done but yet procrastinating it to a later time and then attributing the inability to execute due to the lack of resources or time - especially for items that need the most critical attention.
Narrow-mindedness. The world is changing and evolving everyday. And those who refuse to keep an open mind and embrace change will suffer under the limitations of its old paradigm. The change in mindset is a matter of crossing a thin line, and that makes all the difference. Sometimes all you need is a gentle nudge or push to see a whole new perspective.
Personal delusion. To think and act under the belief that you are someone else. It's ok to have dreams and ambition but don't wear shoes that are too big for you or make promises that you can't deliver.
Be real and comfortable in your skin. Let learning and the will to act be a way of life.