cause
I didn't listen carefully in class and didn't finish my homework carefully.
Squeeze out time to study math because I like other subjects.
Or you don't like mathematics by nature, and you feel that mathematical operations are too troublesome, so you are tired of mathematics.
improve one's method
Average allocation of study time
Don't think math is difficult, just master the method.
As for mathematics, I think we can learn it well if we have enough efforts and talents. If we lack talent, we should make up for it with efforts.