Why do we need to accumulate experience?

My team recently revised the side navigation component expands/collapse interaction. Initially, the interaction overlapped the main content on the right side of the viewport whenever the navigation was broadened. When we developed the initial version of this component, we had yet to consider what kind of interaction behavior we should apply thoroughly and forgot to consider the application environment.

But after hearing some of the customer complaints, we decided to convert it to take the space and shrink the main content width when the navigation is expanded. After experiencing this, I realized that the side navigation components in desktop web applications usually adopted this interaction, not the overwrapping we naively applied. It's bizarre. I never thought about or paid attention to this, but the experience made me aware of this pattern.

One of my friends experienced a similar thing recently. He told me that he tried some of the workplace's club activities and met some people from outside of his team. After a few meetups, he sometimes encounters or finds out those people among the crowd in the office. They had been working there before he met them or maybe even before he joined the company, but he now perceives them.

Learning a language feels the same. After each class, I learned new vocabulary, phrases or sentences, and even culture, and suddenly those things are living and breathing near me. I felt helpless about the Japanese language in Japan even though I keep learning in Korea. So I just went outside and dealt with the actual situation as much as possible to learn the essential language skills for surviving in Japan.

We understand knowledge by the head. We know that the side navigation should not degrade the user experience. Still, it's easier to make a correct decision or perceive the phenomenon clearly if you have more experience making your body feel and remember it. It's like the difference between assuming the contents of the jar only by looking at it from apart and opening the lid to handle the actual content. But we can be wiser about guessing without opening it after testing some rotten contents.