I think the very best thing I did for myself in 2014 was learn to understand how the human body processes calories and weight. Knowing how the process works has helped me carve out a fitness and diet routine that works for me, and has taught to rely more on how my body works and feels than what the scale says.
For example, when I stepped on the scale yesterday, I was surprised to see that I was weighing four pounds more than I expected to. At first, I beat myself up for all the holiday partying I did. But then, I remembered that I had just completed my first leg muscle training day in almost two weeks. And that I almost always put on exactly five pounds of 'muscle weight' when I return to this massive muscle group after long absence. The weight can take up to a week to come off, but once it does, it usually sheds extremely quickly and tends to take a few extra pounds with it.
Sure enough, I weighed myself this morning and found that I was almost three pounds lighter than I was yesterday. Now, clearly I didn't deficit myself by the 10,500 calories I would need to in order to lose three pounds that quickly. But I did start to lose some of my water weight from the muscle work, as well as some of the bloating that accompanies following an unusually rich diet.
The point is that it isn't what the scale projects over a 24 hour period that makes a difference. It is what it projects over a lifetime- and the amount of change that appears not only on the scale but on your actual body that matters. The scale is like a photograph shared on facebook- a good image to bear in mind, but harldly representative of the whole picture. :)