We've practically set ourselves up to fail - we have "back doors" and loopholes in every part of our lives that allow us to simply give up or back out of our commitments and then blame it on some outside force having influenced us to make the choice to back out. There are very few people who have developed self discipline - unfortunately they use that self discipline to enhance their personal goals instead of enhancing global goals to improve the lives of everyone. We have been deliberately kept from learning to have self discipline, as people without self discipline are more willing to do the things they know they shouldn't, because those things are easier. For example: giving a few Rands/Dollars/Pounds/Euros/whatever to a child welfare charity may induce a sense of purpose and well being - but it does nothing to actually stop the abuses and neglect of children permanently - and neither will anyone want to consider that giving money to a charity doesn't actually help to end the larger issue, nor would anyone spend any real time or effort looking into the causes of those issues.
Think about it: none of us are taught how to really commit to and follow through with anything that requires more effort than is deemed "easy". relationships may be one of the most commonly abandoned commitments in our social reality: as soon as the "fire goes out", we are no longer interested in honouring our commitment and really choosing to be with and enjoy being with our partner every day. We are much more inclined to go from energetic fix to fix, looking for the next new lustful high. Another example is the ever expanding size of people in the "westernized" parts of the world. People are far more keen on getting quick meals and TV dinners and chocolate bars than they are in taking the time and effort to prepare a meal. Entire families balloon into whales, and then try to lose the weight by going for the fastest solution, like getting their stomach stapled, which is obviously far more dangerous than simply changing one's lifestyle and eating habits.
Sure, we may want to keep our word. We may want to honour our commitments. We may want to change the world. But we don't. In order for us to develop self discipline, we need to start by actually forcing ourselves to walk that which we have committed to walk - there is no other way.
You can develop your self discipline here and here.