It appears as though there is a cycle of resolution, attention to subject area of the resolution, a gradual slip of that subject area from the fore of ones attention, and the slip in standards.
How long does this cycle last? How does duration vary between people? Do similar resolutions (e.g. diet resolutions) have similar durations?
How many resolutions does the average person make per year?
Does failure of a resolution weaken our resolve in keeping to others (i.e. make other resolutions more likely to fail)?
It seems that there are many interesting questions that can be asked of this subject, and perhaps a need for tools to capture the data to answer them.