Some people have work schedules or lifestyles that do not permit them to irrigate at a consistent time each day. This too can cause irrigation to be unsuccessful. The thing you need to know is that you don't have to irrigate your colostomy in order for it to work Your bowel will work anyway, irrigation or not. The purpose of irrigating is to achieve regulation of the bowel so that no stool is passed between irrigations. The reason for regulating the bowel is for the ostomate's comfort and convenience.
Some doctors use irrigations to stimulate the bowel after surgery.
Some simply assume it is preferable for the ostomate. If your doctor told you to irrigate but you no longer want to, check to see if there is a medical reason for doing so. If there is not, the choice to irrigate or not to irrigate is up to you. You may have to modify your technique and her experienced knowledge can help you. For your own knowledge, here are some general pointers to keep in mind for successful irrigations.