And I've tutored people who simply did not make any appreciable progress in their math skills despite their best effort.
Please don't take this personally, but have you thought about the possibility that some of the students you tutored did not make any appreciable progress because you were not tutoring them effectively? I raise this point because when we talk about their "best" effort (or as you clarified it, substantial amount of effort), they may well be putting in their efforts in an ineffective way. Also, people can approach the same problem from different vantage points (some learn by repetition, others learn by example, still others learn by visualization). If you don't teach or tutor them in ways that customize their particular way of learning, they may not always be able to pick up on the material.
Furthermore, learning isn't necessarily linear. Students can struggle for long periods without making any visible, apparent progress and then suddenly things "click" -- anecdotally I've seen this occur among numerous students.
Many people who have contributed comments here, including me, have reached their own limits in spite of years of effort. I know people who easily went beyond my abilities. I have attributed that to a difference in raw intelligence. When someone says that it would just take me more time I have to remind them that, at my age, time will eventually run out.
I have known for a long time that I have a weaker memory than most people. I often have to derive or be reminded of facts that others can remember without help. That translates into a serious handicap in learning. I believe that this fact is undeniable in spite of what anyone else thinks.
interests change as well. History was one of the least appealing subjects to me at school, and a history textbook before bed was a sure-fire method for me to quickly go to sleep. But I'm starting to pick up my interest in history now, as a grown-up, and finding myself being fascinated by subject, while being able to memorize historical facts (and even the dreaded "dates") better.When a person does math beyond their interest level that is when they feel they are working too hard
IMHO, people who try to blame a single factor for a lack of mathematical ability are just trying to oversimplify a complicated subject. They are doing it without scientific proof and they are ignoring other evidence. This thread is very unscientific.
The impression I get from them is that they are giving a substantial amount of effort for very little progress. Is that a better way to word it?
Is this topic making any progress yet?
Can anyone learn advanced maths? (Researches)
I have no "researches" to refer to. I'd say "advanced Mathematics" might be anything beyond the range of typical university Calculus 1, 2, 3. Below this range of courses may be Algebra 1 & 2, Geometry, Trigonometry, College Algebra (part of "Pre-Calculus"). I'll take Drakkith's statement on it (Can anyone learn advanced maths?). His statement is based on his own learning, and on teaching or tutoring experience. One should try teaching or tutoring, to be more familiar what that is like.