Why the first track matters most
Launch library · evergreen read

The opening song sets real expectations for everything that follows across the rest of the playlist, functioning much like an opening line does in a piece of writing, establishing tone before the listener has even consciously decided whether they want to stay properly engaged with what comes next, a decision that quietly shapes how generously a listener chooses to stay.
A strong opener should genuinely represent the playlist's overall character without necessarily being its single most intense or memorable moment, since its real job is to invite the listener in rather than overwhelm them completely before the rest of the collection has even had a proper chance to unfold, leaving the rest of the set room to build toward something stronger later.
Choosing the first track only after the rest of the playlist has already taken shape often produces considerably stronger results overall, since only at that later point does it become genuinely clear what tone the whole collection actually needs to establish right from its very opening moment, a lesson many curators only learn after building several playlists the hard way.