I attended medical school and excelled in my organic chemistry courses as an undergraduate. In my view, organic chemistry is a difficult course for many because

I attended medical school and excelled in my organic chemistry courses as an undergraduate. In my view, organic chemistry is a difficult course for many because it is quite multidiscplinary and requires multiple modes of thinking/reasoning. - Basic chemistry (chemistry 101): Concepts like bond formation, electronegativity, acid-base reactions, etc - Memorization: Functional groups, reaction types, etc are fundamental building blocks (much like writing and speaking requires a knowledge of words). - Deductive reasoning: Getting from molecule A to molecule B requires long chains of intermediate steps that logically follow from previous steps - Visuo-spatial: This is probably the one faculty that comes naturally to some and absolutely does not click for others.. Understanding organic chemistry fundamentally requires an appreciation of how molecules and groups interact in 3-D space. Understanding spatial patterns and interactions also helps with memorization (e.g. it is easier to remember why certain functional groups behave the way they do) - Linguistic: This may seem trivial but many struggle with the grammar of naming molecules (IUPAC nomenclature) It is true that organic chemistry is a weeder course for pre-meds. However, I do think it is a relatively good filter to select people who excel across multiple cognitive dimensions, which is required for success in medical school. Now whether or not this is required to produce good doctors can be debated, but I suspect that in certain corners of medicine, particularly the more cerebral specialties like nephrology or academic medicine in general, rigorous undergraduate courses such as organic chemistry are absolutely pre-requisite. I ended up leaving medicine and am now a founder of a biotech startup, so take my opinions with a huge grain of salt :)