It's human nature, isn't it? If you give yourself an inch, you're liable to take a mile.
Skip your workout for no good reason, rely on boxes for your family's nutrition, have a "write-off" vacation, a regularly scheduled "cheat" day - there are no shortage of inches out there just waiting to get turned into miles.
Now of course, there will be times where real life does preclude your best intentions and inches are necessarily and understandably taken, but it's the inches for no reason that I worry about.
I blogged once that there are times when suffering's warranted. Another time I blogged about how healthy living requires effort. Both are true, but I can't help but wonder how many folks' best intentions were waylaid by the simple fact that they bit off more than they could chew - that their inches were in fact miles.
Better to take small careful steps of change than to require huge bounding leaps as this race never ends and you really best try not to get tired.