Three things means "many". In this case three lines means "many lines". In view as list, the files are displayed as each file on a line. In justify the text go

Three things means "many". In this case three lines means "many lines". In view as list, the files are displayed as each file on a line. In justify the text goes from being snippets of various sizes to being a bunch of full lines. In drag to reorder the many lines make you think of ribbed texture of that thing you can drag against. In settings when you tap on many lines, you arrive at a screen that has many lines of settings.