For a lot of women it is because they want to avoid all unnecessary intervention, or because they have had a traumatic experience in hospital the first time around. For others there might be totally different reasons. Homebirth is a safe option for women.
Statistics show that it is as safe as hospital birth, even safer.
Countries like Holland, Scandinavia and previously England, where homebirths are common and midwives deliver babies intervention rates are a lot lower and infant mortality rates are lower as well.