One of the biggest causes of under-achievement is the habit of making excuses. Making excuses is our way of shifting the responsibility and/or the blame somewhere other than ourselves. As long as we do this, we give the excuse power over us and our future. Making excuses robs us of our chances of achieving anything significant in life.
More importantly, every time we make an excuse we reinforce our subconscious belief that we are not capable of achieving. This leads to loss of self-esteem and self-confidence, two of the most important attributes we need in order to lead a successful, fulfilling life. Because the problem with the habits is that we do them without thinking, the first step in breaking the excuse habit is to become aware of every time we do make an excuse. We need to mentally catch ourselves and begin to hesitate before making the excuse.
One way to do this is to repeat the following mantra over and over to yourself everyday: "Excuses are useless! They rob me of my success, my self-confidence and my self-esteem. I take action and make things happen!" Repeating this to yourself many times a day will cause your sub-conscious mind to alert you to the fact that you are making an excuse This will help you to check yourself and start recognizing the excuse. Get someone close to you, whose judgement you value, to help you by gently pointing out when you make an excuse. Once you're aware it becomes easier to stop.
The second step is to recognize that excuses are just rationalized lies. I'm certain that no one wants to be thought of as a liar, so start to accept that every time you make an excuse someone will think you're lying. Now that may not be the case every time, but think of it as actually happening. Next time you make an excuse to someone, immediately think to yourself, "They think I'm lying." It's embarrassing, especially if you're making the excuse to someone whose opinion of you is the eye in the mirror and be proud of the person you see, life has little chance of being satisfying.
The third step in stopping the excuse habit is to actively start thinking of the benefits you'll receive by doing what you are currently avoiding doing. Before you make the excuse, now that you are aware of it, take a few minutes to think about all the good things that could happen if you did whatever it is. It could be an improvement in your relationships, a feeling of satisfaction and accomplishment for doing a task, an increase in earnings. The point is, there is always a benefit derived from taking action. Even if it is only learning what doesn't work, it'll save you making the same mistake or wasting the time in the future.
The person who really wants to do something finds a way. The other person finds an excuse.