If that can help, I think anyone who does well in reading as a school subject don't actually read things but skims over it. It's even what we're told to do when preparing for foreign languages exams.

As for math specifically, for me it's always depended on the teacher. It's not one of my bad subject per se but it's also a subject a bad teacher can completely break for me. I need good explanations and once I get it I get it. (And then proceeds to forget it as soon as the exam is finished. I honestly don't remember a lot from my math classes).

My all-time bad subject though is German and I don't understand why. It's the language I've been learning the longest (longer than English) and yet I can barely form a coherent sentence. It's incredibly frustrating.
I should probably go live in Germany for a while but it's not exactly possible right now.

I am a Mathematician so, yes, Maths are easy for me

It's one of those things that you either get the hang of it or you don't.
Such as languages. Yes, they are complely different subjects, but the problem is pretty much the same: if you know what the teacher is talking about then following the instructions is rather easy (not a ton of studying required) but if you don't know what the teacher is talking about then you are completely and absolutely lost, with nothing to grab that may help you to get started.

Fixing it is not easy though.
Teachers may try to present the lesson in several different ways, hoping that one resonates with you. Hoping that something will go *click* in your mind and the pieces will start falling into place as a puzzle.
But if they don't find anything that resonates with you then they are quite lost too. Because they don't find a way to "translate" what they know into something you would understand.

That's a terrible thing for a teacher to say
(I personally consider that kind of attitude innaceptable.)

I've had students with some issues with the subject.
I always like explaining where everything comes from, what's the explanation or the reason for everything, because that's what I've always loved about Maths.
Some people find it obscure and confusing, and for those students I tend to explain things in a way you can memorize - even if you don't understand a word. It's an awful way to study maths, but at least they'll be able to pass their tests.

I had a few of these teachers as well. Sometimes they just didn't have enough time to go through everything a few times for everyone who didn't understand. It's sad because since I usually finished everything early I'd try to help these students instead and most ended up understanding enough to pass the exam. Just needed more time and personalized explanations.

Moi wrote:

Kuuki: Really 8u
I assumed that most people actually read stuff and I was just lazy xD;
I hate reading and I especially hate reading stuff that's not interesting to me.
Just skimming over it and using common sense got me through quizzes and tests.
Like if the story was about a dog, then the right answers would revolve around dogs ._.

I would love to learn German. My grandma was from Germany. I wish I had asked her to teach me ><

Nope. Don't worry, not lazy, just efficient. Or maybe you're (we're) efficient because you're (we're) lazy.

But seriously, when the objective is to pass an exam you're getting more points by actually finishing the exam than by reading everything carefully and not having the time to go through everything because of that. You can still go back to read again later if you have time.

Moi, algebra is evil and should never be taught beyond the basics of it, imo. Geometry is much more applicable to daily life, again imo.

I struggled so hard with algebra because it just didn't 'click' in my head. I did much better in geometry because I could see how the pieces fit together. I'm a visual learner, mixed with learning by doing. I drove so many teachers to frustration, it's not even funny. All because I couldn't learn the way they were teaching.

In your case, it may be similar.

Math for me was also very much on a teacher-by-teacher basis for the first few years. Then I started to figure it out and could ignore the teachers and learn it on my own, but those first years? Those first years were entirely at the mercy of chance as to whether that particular teacher was teaching in a style that worked for me or not.

One thing I did find super helpful was whenever I was struggling, I'd go find someone and try to explain it to them.
Not have them explain it to me, but have me explain what little bits I did get, to them.
Then I'd just start exploring it.
Like...
This is, as best I can reproduce, a soliloquy that my poor family had to sit through when I was young:
"Okay, two year old brother who doesn't understand math at all but who loves me and will listen.... let me tell you about what I learned in school today.
"I have this napkin. See? Look. Regular paper napkin.
"And I can tear it into two pieces and now I have two halves, and if I give you one, that's fifty percent somehow even though it's just 2 pieces and not 50.
"...
"Okay I don't get that but let's move on.
"Wait no, hang on.
"If I tore it up into 100 tiny little pieces, that's 100 pieces to make 100% even though now it is in bits and not whole, so I guess percentages don't measure how whole something is, just if it's all there or not?
"Wait don't eat the napkin half, have an apple and give me that back.
"Yuck, this is all wet and icky now, let me get a new napkin.
"And then tear it in half again but this time you don't get half, just keep eating that apple.
"Okay.
"Supposedly if I counted out those 100 pieces I'm not going to make into two piles of 50....
"then it would be the same amount of napkin as the half I have right here from tearing it into 2.
"So maybe that's why it is 50 percent?
"But why do we use 100 anyhow and not 10? Why couldn't I say I tear it into 10 pieces and then a half a napkin is the same as 5 of the pieces of the 10, and it would be 5%? And that would be half?
"Percentages don't make sense.
"Is this one of those stupid arbitrary things that people just randomly agree on, like, okay, we're just going to *declare* that the natural thing to do is tear stuff into 100 pieces? And then they build other stuff and make new rules based on that?
"People are stupid.
"Wait I'm a person I don't want to be stupid.
"Okay people aren't stupid we're just weird.
"Yeah, weird is okay.
"So percentages are always based on 100 of them. What if it's like time, though? An hour gets cut up into 60 pieces instead of 100. I know that! That's called minutes and it's the long hand on a clock. So is half an hour still fifty percent or is it... wait what's half of 60. Hang on.
"...
"Okay I'm done counting half of 60 is 30. So is half an hour still 50 percent or is it 30?
"Mom, my brother is useless! Tell me what half an hour is!"

Etc.

But it really helped me pin down what I knew, and what I didn't know, and the best part was it helped me figure out which bits of math were logical and you could reason them out, and which bits of math were not logical at all and you just had to memorize them.
(People who said math was all logic were not thinking logically, in my opinion.)

You might have dyscalculia.
I have it and so does my mom, I think.
Not diagnosed.
but its pretty much dyslexia but about numbers instead of letters and words.

I think skimming is good for technical books, but literature needs to be read thoroughly and analyzed, but to be fair you can get away with just skimming.
just let others analyze it.
but i always thought that was fun.

one thing is huge literary and technical works that are filled to the brim with meaning and big words can take forever if you DONT skim.. but you wont understand it as well.