The increment of the commodity which he is only just induced to acquire (whether by... direct labor or by purchase) may be called its Marginal Increment; because he is on the margin of doubt whether it is worth his while to incur the outlay required to obtain it. And the benefit-giving power, or Utility, of that increment to him may be called the Marginal Utility of the commodity to him.

Over time, the Accumulation of small helpful or harmful behaviors and inputs produces huge results. According to Lean Thinking, by James P. Womack and Daniel T. Jones, Toyota’s approach is based on the Japanese concept of kaizen, which emphasizes the continual improvement of a system by eliminating muda (waste) via a lot of very small changes. Many small improvements produce huge results. Accumulation isn’t always positive. Think of what would happen to your body if you consumed nothing but fast food, candy bars, and soda for a decade. Eating a single candy bar isn’t a big deal, but eating hundreds of candy bars is. Fortunately, the opposite is true as well: small improvements in your diet, a little more exercise, and a little more sleep can have major effects on your health over time.

We must always strive to improve, little by little.

Being in the GAIN means you measure yourself backward, against where you were before. You measure your own progress. You don’t compare yourself to something external. You don’t measure yourself against your ideals.

I like being on the margins. You work better there.

Develop the winning edge; small differences in your performance can lead to large differences in your results.

Your margin is my opportunity.

Every joy is gain
And gain is gain, however small.

A fundamental aspect of being in the GAIN is to live your life in a self-determined way. You stop living in the GAP and measuring yourself based on ideals, but rather live based on clear measurables that you yourself have chosen.

The general theory of economic equilibrium was strengthened and made effective as an organon of thought by two powerful subsidiary conceptions — the Margin and Substitution. The notion of the Margin was extended beyond utility to describe the equilibrium point in given conditions of any economic factor which can be regarded as capable of small variations about a given value,or in its functional relation to a given value.

The hope of a positive expected gain lies in detecting a wheel with sufficient bias.

Small things matter when they accumulate. This is one of the main lessons of my work—and one of the principles I try to follow in my life. The details, when finely polished and carefully combined, add up to something remarkable.

Practice mental subtraction to remind yourself of the GAINS in your life. Create a GAIN Tiny Habit Recipe for getting out of the GAP, such as the five-minute rule the women’s soccer coach used.

There's no great loss without some small gain.