Compressor Export Setting - Dithering - check or uncheck?

Hello,

Please does someone have more information about Dithering?

In Compressor Help I could only find:

• Dithering: When selected, adds a certain type of noise to images to prevent large-scale distracting patterns such as color banding. If your image has excessive noise after rendering, deselect this checkbox.

The inbuilt Compressor presets don't use it.

How would this "certain type of noise" look?

I tried it and could not see "excessive noise" afterwards, so I kept this setting,

but what are the advantages/disadvantages?

Honestly I couldn't see a difference (maybe just in my case, footage of forest, many leaves).

Also, does it add a lot to the rendering time?

Many thanks!