There's a subtle shift that happens when a hugely successful pop star becomes more than just a pop star, and it's not always identifiable in a particular song. With Madonna, for example, it happened over the course of the Like A Virgin album; with Michael Jackson, it was obviously Thriller; and with Britney Spears there was no shift, she was always top-of-the-world from the first single. I'm not even particularly confident that this particular song marks Luis Miguel's shift (it could well be the 20 Años album, which broke sales records for Latin Pop from the first week of its release, but which I haven't heard in full) — but his music has definitely moved up a tax bracket since last we saw him.
But it's not just the production, as expensively glossy, spacious, and upscale as we've heard to date (at least this side of Julio Iglesias) — Miguel's singing has lost its teen-pop floridity, the anxious emotionalism of "Fría Como El Viento"or "La Incondicional," and he sounds now like a man supremely confident in his powers, able to work in delicate shades of timbre and phrasing without sacrificing the full-blast power of his gifted lungs.
That top-of-the-world atmosphere is perfect for this song, the kind of song a William Randolph Hearst might sing while pursuing his Marion Davies. The title means "I have everything but you," and while he isn't so gauche as to detail the extent of his holdings, Miguel's performance is that of a powerful, wealthy man missing only the one thing that won't be his for the asking. The alto sax coming in at the end was a signifier of opulent classiness as the 80s turned into the 90s, but it was also, at least for those whose palates considered themselves more refined, a signifier of the bourgeois failure of taste — anyone who remembers the 90s as they actually were (rather than as they were played on TV) hears Kenny G, and winces.