If you want to be a person who is known for integrity and keeping your commitments, the first step is truly considering what it is that you are committing to before you make the commitment.
In Luke 14:28, Jesus asks the question "for which one of you, when he wants to build a tower, does not first sit down and calculate the cost to see if he has enough to complete it?" I think we would do well to use that line of thinking when making all of our decisions regarding where we do or do not make commitments.
We get so caught up in the moment sometimes, overwhelmed with emotion that we set super lofty goals or tell others we will do something for them without really taking a moment to consider what that commitment will cost. We have all done it!
Please hear me - I am not saying don't make commitments. I am not suggesting that we do not set goals. I am not saying that we never step up and take responsibility to complete a task. I am simply saying - before you do - make sure that you are willing to do whatever it takes to make it happen. Consider the cost - emotional, mental, physical, time, monetary, etc. If you cannot say "I am willing to do whatever it takes to make this happen" it would be better for you to not commit.
When we make commitments that we do not keep - not only does it destroy our credibility and integrity with others, it affects how we feel about ourselves. We may not even realize the subtle way it affects us, but over time, the broken promises, the goals un-achieved and the projects not completed pile up and they cause us to lose confidence in ourselves.
It is better to commit to something smaller and follow through than to commit to something awesome and fall short.
Become a person of your word, a person of integrity, someone others can trust and depend on by being careful, thoughtful and considerate of the cost of a commitment before you commit.