Why is there a placeholder graphic before playback of videos on Android devices?

This is an Android caused issue which appears widely across many apps (including YouTube and Facebook on Android devices). It might not be displayed each time before playback of a video but in most cases when you press "Play" there is a brief placeholder graphic on Android OS devices. Unfortunately this is outside of Lightcast's or any other app developer's control but a behavior which happens on many different media platforms on Android devices.