What you describe is known as Selective Exposure to Information.
Selective exposure is a theory within the practice of psychology,
often used in media and communication research, that historically
refers to individuals’ tendency to favor information which reinforces
their pre-existing views while avoiding contradictory information.
Below find extracts from this article about selective exposure:
The researchers found that people are about twice as likely to select
information that supports their own point of view (67 percent) as to
consider an opposing idea (33 percent). Certain individuals, those
with close-minded personalities, are even more reluctant to expose
themselves to differing perspectives
Perhaps more surprisingly, people who have little confidence in their
own beliefs are less likely to expose themselves to contrary views
than people who are very confident in their own ideas ...
The researchers also found, not surprisingly, that people are more
resistant to new points of view when their own ideas are associated
with political, religious or ethical values.
The above article is based on this research article.
A very related theory is the confirmation bias.
Confirmation bias, also called confirmatory bias or myside bias, is
the tendency to search for, interpret, favor, and recall information
in a way that confirms one's beliefs or hypotheses, while giving
disproportionately less consideration to alternative possibilities.
In my opinion the reasons why we employ selective exposure are:
- Preserve and form identity
- The need for certainty. We need to have firm theories that do not change whenever we encounter dis-confirming evidence.
- Competence. The need to have good skills i.e. fishers forum