"Analogous" Quilt

I recently came across this photo of an "analogous" quilt...

The term " analogous" had me turning to google - and then to some of my painting notes.

Analogous quilts have colors next to each other on the color wheel... like red,  orange and yellow; red, purple and blue...

Analogous colors apparently create a relaxing mood...

I don't fully understand the concept - but I'd like to try making an analogous quilt sometime myself.