How To Score Full Marks In Mathematics Test

For in much wisdom is much grief: and he that increaseth knowledge increaseth sorrow. (Ecclesiastes 1:18 KJV)

To score full marks in mathematics test, just answer every question correctly. It sounds simple and logical. So why isn't everyone scoring full marks?

Lack of knowledge - you do not know how to solve the question;
Lack of ability - you know, but you may not know it well enough to solve it within the allotted time.

To be perfect, one just need to do everything right, right view 正見, right intention 正思惟, right speech 正語, right action 正業, right livelihood 正命, right effort 正精進, right mindfulness 正念, right concentration 正定. Then why are we not doing it?

Lack of knowledge - we do not know what is right;
Lack of ability - we know what is right, but do not have the ability to do it perfectly;
Lack of agreement - we know what is defined as right, but disagree with that definition;
Lack of will - we know what is right, but we do not want to do it, we want to do it our way.

For I do not do the good I want, but the evil I do not want is what I keep on doing. (Romans 7:19 ESV)