We often pass exceptional service design throughout our day without even noticing it. One such process/design is that of the BART announcements. Whether you are a regular traveler or not, your subconscious mind will get attuned to the way the announcements are made. All trains moving from the East Bay to San Francisco / Daly City have the voice of a lady announcer, while all the trains going towards the East Bay have a male voice announcer.
Knowingly or unknowingly our subconscious minds make that connection and travelers going to the East Bay will be more focused when a male voice is making announcements.