Sometimes the design of a web page just seems off. No one can put a finger on it. The layout of the screen makes sense. The separation of data is well proportioned. There isn't a lack or overuse of color. Yet, the web page doesn't feel inviting. This might be the fault of human nature and a psychological force called Contour Bias. The principle states that humans have a tendency to favor objects with curved contours over objects with sharp angles or points. Knowing this preference, take a second look at the web page. HTML elements such as divs and spans are "squarish" by default. Does the design have contours or simply lots of boxy edges? Does the site feel manufactured?