Even in highly realistic depictions, people are adept at spotting the smallest inconsistencies in a robotic or animated humanoid. 

These relatively minor divergences can make a character go from lifelike to uncanny. In one of Mori’s original examples, a robotic character was seen as unlikeable and creepy when it smiled slightly too slowly.

In these and other examples, being close to human in appearance does not produce affinity with the characters among viewers. When characters fall into the uncanny valley, people instead perceive the characters as cold, vacant, and soulless.