What is true about office friendships

The truth about office friendships is:

Workplace cliques can cause horizontal disharmony.

Clique is a small group of people who share common interests and usually spend time together and do not readily allow others to join them.

Workplace cliques can cause horizontal disharmony because they are purposefully alienating others. People within a clique uses said clique to be their comfort zone. Thus, they do not extend effort to meet and cultivate new friendships nor exert effort to do better at work. Sometimes, they tend to pass up promotions or better benefits so that they will stay within their cliques and not deal with insecurities or feel vulnerable in facing situations that they are not comfortable with.