Mostly, first group were people who did not paid attention or were not used to think for themselves. Plenty of times it takes like 15 seconds to find the answer if you think about it. People who don't bother to think rarely start to be able to figure out on more difficult concepts by the end of the class. The dichotomy between people who ask simple questions and the ones who don't care is false one. There is massive group of people who think for themselves at least a bit when they come across issue.
"Senpai notice me" people tended to be orthogonal to quality of knowledge or willingness/ability to explain. Full disclosure, I asked these questions when the "participation" was necessary to get points. It is a bit stupid when you know answer, but still needs that participation point ...
None of that has anything to do with quality of lecturer.
I'm not very competitive. In American culture, that makes me a "reject," but I have always felt that I need to get by on my own merit; whether or not that compares favorably to anyone else.
People who know more than I do are not "competitors." They are resources.
The biggest issue that I have with people (and I am guilty of this, myself), is the tendency to ascribe motive to behavior.
In my case, I'm dead wrong -a lot- (See "on the spectrum," above). I've just learned that my projections of motive are usually wrong, so I have come to ignore them, and concentrate on the facts that are on the table (as opposed to in my head).
If I want to impress the teacher, I do good work. If I want to learn the topic, I ask questions to resolve gaps.
It really is that simple.
A class is just a transitory experience. If I fail to learn the subject matter because I'm afraid of what these people that I'll probably never see again think about me, I have no one to blame but myself.
One reason is that I am not afraid to ask questions about why something is. I need to learn my subject "to the bone."
At the start of class, I'd always be asking questions that would have facepalms and guffaws around the room.
By the end of class, I'm helping everyone to figure the material out.
The best teachers I ever had were trained teachers; not subject matter experts.
The absolute worst teachers I ever had were subject experts. They would routinely skip important fundamentals, and shame you for not knowing them. I guess that they assumed we would be able to figure it out on our own; which isn't a bad idea.
Except when they don't give us the time or access to resources required to learn.