Sundays, Patterns Galore
Making Eyes At
A simple enough pattern like a checkerboard gives the eye (and hence the brain) a calming sense of order.
The dervish chaos of a paisley* pattern is equally made of identical units that will seamlessly repeat from your front door to Kansas, but your eye cannot readily read the units’ traveling outlines. Their cookie-cutter shapes dance willy-nilly without steady squares to settle on.
* I regret that Wikipedia has chosen such low-quality examples for illustrations.