Contrast with value means the intensity of brightness or darkness.

Leading the viewers' eye to an important area of the frame creates emphasis. 

With these icons, there's no contrast of value. No value change means no focal point.

Where should the eye look?

The other grey squares recede, and the white icon is dominant.

It's easy to see what's essential for the viewer. 

The white triangle lifts off the page because it's the brightest element. 

All the other circles recede into the background.

As you change the lightness and darkness, you change where the viewer will look. 

Shape and value make the love heart icon stand out. 

Using value will help your designs if you have a busy background.

A greyscale row leads your eye from bright to dark.

When the background changes to white, the greyscale values lead your eye. 

Emphasis and importance have changed.

Mix value and scale to supercharge contrast and focal point.

The triangles recede into the distance as the values step down from light to dark.

Here it's clear where the viewer should be looking. 

Light and dark combinations work well with type. 

A darker headline allows the lighter type to lift off the background and create emphasis. 

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