You are reading something, and a technical term is used. It is just one more word so why should it be confusing?
Sometimes, that is all it is.
Other times, however, it can be unclear whether it is a technical term. This week’s Odd Language (Not on the Level?) is an example of this. Due to the ambiguity of “tier” – level or something that ties? – I was confused.
Another way to get confused is acronyms. I recall reading a USENET post that had an unfamiliar acronym. There are a number of Websites that have lists of acronyms and what they mean. I looked up the acronym and found just over 100 expansions. Which one applied? Who knows? If one knows which area the acronym comes from, one has a reasonable chance to figure it out. If not though, it is much more difficult.
Common sense is very useful, but only if one has it. Common sense depends on a lot of knowledge about how things work. If you know an area, you have common sense in that area, and things are “obvious”.
The kicker is that if you do not know an area, you do not have much common sense in that area. This is one reason why it can be so difficult to get started learning in an area. You lack basic knowledge in the area. Searching for information is very difficult when one does not know what things are called.
This issue has little to do with intelligence. It is a knowledge issue.
If you see someone having trouble understanding an area, it might be that the person lacks a roadmap. If you know that area, please remember that what is obvious to you is not necessarily obvious to someone who does not know that area.