Answer:
Human error
Step-by-step explanation:
The typical-use failure rate takes into account that the human error is inevitable for a contraception method been used by a human. the use of contraceptives are highly effective in the prevention of unwanted pregnancy and sexually transmitted diseases such as HIV,Syphilis and the others.
In the typical-use failure rate the Human error is very important because although the contraceptives might be good and effective if not properly used it would must likely fail and result to unwanted health issues.