Using your own words, explain why the apr does not compare loans for different lengths of time.

This may be your answer
Some classes of fees are  not included in the calculation of APR. Because these fees are not included,as  some consumer advocates claim that the APR does not represent the total cost of borrowing.
 Excluded fees may include: routine one-time fees which are paid to someone other than the lender and penalties such as late service  without regard for the size of the penalty it will be imposed