Courtesy of Roxanne Ardekani
Jason Henry for BI
This as-told-to essay is based on a conversation with Andrew McCollum, the 42-year-old CEO of Philo, based in San Francisco. It's been edited for length and clarity.

Though open earbuds share the common feature of sitting on the exterior of the ear, they come in many shapes and sizes, from clip models to ear hook models.
AP Photo/Markus Schreiber