It's easier to reflect back over the course of a year than it is a single day in one's life. Even corporations have quarterly reviews and annual reviews. I can't think of many goals where the strategy is to measure one's accomplishments on a daily basis. Even with weight loss most programs will tell you weigh yourself (once a week) instead of daily.
You have to give a plan (some time) to see if it will work. Changing directions based upon the pervious day's events would drive most people crazy! Maybe 90 day resolutions would make sense on a personal level. :-)