We complete the incomplete. When confronted with an irrational shape we try to rationalise it.
When looking at a complex arrangement of individual elements, humans tend to first look for a single, recognisable pattern. (Rutledge A, 2009)
In interface design, this innate desire to complete objects and shapes is leveraged on mobile devices, where space is limited. Horizontal lists are intentionally clipped to encourage users to scroll horizontally to view more content.