UI Design and How to Make It Human-friendly

People may notice many apps with UI placed at bottom instead of top, for example, Windows taskbar, status bars in many apps, macOS dock, notification, chat boxes, buttons on websites, and many others.

There is possibly a reason for it, that human eyes look downward easier than look upward, and especially when the info to show on UI is status to see while working with something else.

Even in games, the UI (non-3D) elements of games should be placed at bottom and it's easier to see while playing with the concentration on the 3D contents at centre.