Automatic doors are useful in a huge variety of settings for many different reasons. One of the most common reasons for installing them is to improve accessibility and mobility in a building. For wheelchair users or other people whose mobility is restricted (such as those who are disabled, elderly, pushing a pram, or carrying heavy loads), an automatic door makes getting into and around a building significantly easier.
Hygiene is also a common factor. Imagine how many people touch a door handle in a busy building every day. In environments where hygiene is a priority, such as hospitals, laboratories, and care homes, automatic doors can eliminate the risk of contamination through the sharing of surfaces.