Is more of something good always better? The inverted-U graph says no, not always.

An inverted-U graph is a curve that models the point at which something “good,” like money or effort, starts to make a situation worse.

Learn why it’s useful in predicting the point at which you might have too much of a good thing.

Most of us tend to believe that when something is good (like strength, money, or small class sizes), more of it is better. But Goliath’s abundance of size, strength, and weaponry didn’t protect him from David’s rock–it made him more vulnerable. There is a point at which the accumulation of resources ceases to be an advantage and another point at which those resources become a distinct disadvantage. The visual representation of this theory is the inverted-U graph.

### The Inverted-U Graph

When you graph the relationship between, say, parenting success and money (an example we’ll explore more below), the shape is an upside-down U.

The tendency of graphs toward an inverted-U shape shows us that many things we think of as unequivocally advantageous, like money or material resources, aren’t. Nothing is good, evil, or even neutral. An item’s value often depends on how much of it you have. It’s advantageous until you have so much of it that its value becomes neutral. At the point of overabundance, its value goes from neutral to negative. What was an advantage in a limited amount becomes a disadvantage in a large amount.

Let’s see how this plays out in an example.

## Inverted-U Graph Example: Money and Parenting

Picture the inverted-U graph. If the X-axis is wealth and the Y-axis is the “easiness” of parenting (0 being not easy at all), poverty is located at the bottom left of the curve. If you live in poverty, it’s harder to be a good parent. Spending long hours at a demanding job is exhausting and leaves you little time or energy to spend with your children.

An increase in money makes parenting easier…to a certain point. Then the benefits start to diminish in proportion to wealth.

Perhaps surprisingly, there’s a point at which the wealthier you are, the harder parenting is, and the curve makes its downward slope. Let’s look at the inverted-U graph:

Why would having a lot of money make parenting harder?

Let’s look at why the seemingly faulty logic of the inverted-U graph actually makes a lot of sense.

You probably want to raise kids who understand the value of hard work and the fulfillment it brings. If your child asks for a pony, and you don’t have the money for one, it’s relatively easy to say, “No, we can’t afford that.” It’s the truth, and there’s no decision to make: buying a pony is not an option.

### Anecdote: The Hollywood Power Player

One unnamed Hollywood power player is very aware of the logic of the inverted-U graph and how his wealth is a disadvantage for his children. He grew up in a lower-middle-class neighborhood in Minneapolis. If he wanted new shoes or a bike, he had to pay half, and to get the things he wanted he became an entrepreneur at age 10, paying neighborhood kids to shovel snow and rake leaves for residents. He worked throughout college, business school, and law school, and climbed his way up the ranks in Hollywood.

He attributes his success to the values he gained from growing up without financial means and working hard for everything he attained. Now a multimillionaire, he knows his children won’t have to work for what they want the way he did. He believes that his children will be less ambitious and won’t know the value of money or even their self-worth.

The inverted-U graph can represent many relationships. Knowing our lives often conform to its curve, remember that it’s possible to have too much of a good thing.

Inverted-U Graph: More Can Be Worse

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#### Amanda Penn

Amanda Penn is a writer and reading specialist. She’s published dozens of articles and book reviews spanning a wide range of topics, including health, relationships, psychology, science, and much more. Amanda was a Fulbright Scholar and has taught in schools in the US and South Africa. Amanda received her Master's Degree in Education from the University of Pennsylvania.