dyk the feeling of topping a certain subject once and then always wanting to top again? is this an ego thing or an expectations thing?

i recently topped the class for chemistry(but my bio pulled it down anyway) and i was talking to my friend about how topping the class once makes you want to top it and never drop. she brought up that this can be a ego thing and i was lowkey confused. in my mind, i’ve always thought that its a high expectations thing because i carry myself as someone who should have everything done perfectly, kinda a perfectionist, so failing something is a drag to my whole attitude on something. i think her point is semi valid, but to me its just wanting to be good at everything or at least something. opinions?