If letter A stands for 1%, while B for 2%, C for 3% and so on so force till Z for 26%. Whatever we plug in these for the word knowledge, or happiness and some similar ones, they will never get 100%. Only we do this for the word attitude, it will work, which means perfect.
If the A, B, C. ... Z representing 1%, 2% 3% .. 26%, whether it is knowledge, happiness and so on, can add up to equal 1, and the attitude is precisely equal to 100% of the combined, It means a complete, perfect