The Asch Experiment is another famous example of social conformity in group situations. One subject was placed in a room with other people, actors who had been previously instructed how to respond. The person conducting the experiment held up an image with three numbered lines and asked each person in the room to identify the longest line.

The actors responded first, purposely choosing the incorrect line, making a blatant and obvious error.  The results showed that, on average, 32% of subjects who were placed in this situation went along and conformed to the clearly incorrect majority, again showing how readily people tend to conform in group situations despite the evidence in front of their very eyes.

When they were interviewed after the experiment, most of the subjects said that they did not really believe their conforming answers, but had gone along with the group for fear of being ridiculed or thought "peculiar".  A few of them said that they really did believe the group's answers were correct.

Apparently, people conform for two main reasons: because they want to fit in with the group, and because they believe the group is better informed than they are.