Someone who spent 5 years perfecting his A-Level Medical Skills; A D-Level doctor in one year; D'S GET DEGREES, RIGHT? This is an extremely hyperbolic situation, but it's more important that you learn to master (to some extent) your skill or knowledge of something, rather than rush through a subject to get by. Do not feel shamed or pressured by our education system if you can't "get" a subject that your peers seem to pass easily. Chances are, someone may be struggling in a subject you easily understand! Learning is a journey, not a rushed process.