In summary, parents, peers, teachers, media members, politicians and religious leaders are only human, and they sometimes make mistakes, or seek to persuade rather than to educate. When this happens, people end up with cultural knowledge that is inaccurate, even though everyone around them may insist that it is right. The situation can lead people to feel they must become like the child in the old children's story, "The Emperor's New Clothes" who bravely pointed out that the king was naked, when everyone around him was insisting on the fiction that he wore a beautifully tailored suit.
It's not always the teachers that are the source of inaccurate knowledge either; Sometimes it is the students. Teachers may communicate correct information, but their students (the people who are absorbing cultural lessons) may misunderstand what is said and form wrong impressions.
However you might arrive at having mistaken or wrong understandings about how things work (including how your problems work) isn't so important. What is important is that you understand that any mistaken understandings you have are likely to result in you drawing wrong conclusions about how to best fix your problems. If this happens, your self-help efforts are likely to be ineffective, or possibly even harmful. It is a good idea, therefore, that you take some time to examine your cultural understandings (your beliefs, attitudes, and understandings) early on in your self-help process so as to make sure that they will be useful to you.