People have trained you to care about how they think because it's important to most people who are living conditionally for you to create conditions they can live with. Abraham-Hicks
You have been trained to accept everything that you believe. The majority of your ideas and attitudes have come from someone else; your parents, teachers, religious doctrine, authority figures etc.
Conditional thinking ... 'A state of mind where people act without fully knowing what they are doing. Similar to habits.' Urban Dictionary
What is happening is that you do things by rote. Simply stated, you were raised to put your socks on first, then your pants. You will continue to do so until or if you are given a reason, that you can justify, to do otherwise. This holds true for everything you do, there is often no thought process, it's just done automatically.
And then, one day, the light comes on, something was said, or you read something that strikes a cord with you, and you start looking into it. This can be life changing, and all it takes is questioning your ideas/beliefs. You will find that some are feasible, some outdated, and some just plain silly. You will be amazed at how much you do with no idea as to why you do it. Just be aware, find out what works for you today. Once you are an adult, you are not obligated to continue with beliefs that you didn't establish yourself.
"Our core being is frequently covered up by our ego and conditioned mind. When we peel away the layers of conditioning we get in touch with the fundamental state of existence which is pure awareness."