Prince is, in spite of famously being a perfectionist, not actually a musical artist whose appeal generally centers around his perfection. Most of his best songs--pretty much anything off of Purple Rain is a good example of this--center around Prince warping a relatively basic song around his own personal eccentricities and tastes.
Take, for instance, "Let's Go Crazy"--it's a great song, but it's not perfect. No pop-rock song needs to have a spoken-word intro meditating on the meaning of life and the afterlife, and no song tailored towards Top 40 radio is supposed to conclude with a blistering, unapologetically pretentious guitar solo of sheer "I'm the best damn guitar player on the planet and if you disagree because I'm a 5'2" scrawny black guy wearing purple stilettos I'm going to prove you so damn wrong right now" audacity. Don't get me wrong--"Let's Go Crazy" is awesome, but it's not perfect. Arguably, it's its lack of perfection that makes me love it. Similarly, look at "When Doves Cry", a song which, if your only exposure to it is through the radio, you may not be aware is nearly six minutes long. It has really cool pop hooks, even if it's done in a minimalist way, but the second half of it gets weird. The album version of "When Doves Cry" is a fine song from the beginning but it takes so many twists and turns that it won't be until a dozen times or so that it really hits you just how dense it is.
"Kiss", however, may be the single most perfect pop song in the rock and roll era.
In 1987, Michael Jackson released Bad, in which Michael Jackson does, for all intents and purposes, an impersonation of Prince. As somebody who prefers Prince to MJ, I'm perfectly okay with this--as immense of a talent as Michael Jackson was, I tend to prefer the rougher edges of Prince, so to see Michael Jackson move a bit more in that direction is fine by me. But in 1986, Prince made a bit of a move towards Michael Jackson, the King of Pop, after years of being the dictator of his own, weird little musical municipality known as the Minneapolis Sound. That move was "Kiss".
"Kiss" opens with nine chiming guitar notes before any other instrumentation or vocals are to be heard. It sets the stage for the frequently overlooked guitar work on the song--it doesn't have a long guitar solo like "Purple Rain" or "Little Red Corvette" but it holds the entire song together. And it draws inspiration from some of the seminal guitar stylists of the era--Johnny Marr, Peter Buck, Bernard Sumner--men on the fringe of the musical mainstream whose chiming, eccentric guitar playing allowed them to be more influential than popular. Of course, Prince was already a megastar by 1986, so he was allowed to do this sort of thing while being massively popular.
Once the intro is over and the vocals kick in, two things are immediately noticeable--Prince's karaoke staple falsetto vocals, and to a somewhat lesser extent, the understated and sparse guitar riff buried low in the mix. The vocals, as an extension of Prince's voice in general, are often mimicked. It's so common to hear a 21st century singer go for the highest notes that it's easy to forget that this wasn't always a pop staple. Prince didn't invent this extreme nature of high-pitching singing--he certainly drew from Stevie Wonder, who drew from Little Richard, and so it goes to the beginning of music as an institution. But the next time you hear "Blurred Lines", listen to the first verse, and come back and try to convince me that Marvin Gaye was the vocal legend that Robin Thicke was mimicking. And as far as the guitar: it manages to somehow, inexplicably be both dense and minimal. The riff is so simple and there's so little else going on in the song and yet it still manages to find the background. It's less a part of pop music and more a staple of most experimental forms of rock--I'll take this moment to interject how Trent Reznor has cited Prince as one of his main inspirations when he was recording the first Nine Inch Nails album Pretty Hate Machine.
Bet you didn't think I was going to simultaneously call a Prince song his attempt to write a true pop song as well as Prince inspiring one of the weirdest, darkest alternative rock icons of the 1990s, did you?
The chorus, sung in three unique styles by Prince--first, in a relatively straightforward manner; second, venturing into falsetto; and the third, with Prince going full-fledged James Brown and screaming his ass off. Lyrically, the song isn't poetry, but that doesn't mean the song is imperfect; the song isn't meant to be a poem. Critics tend to fall into the trap of construing complex, meaningful words as an asset when often times, they're a distraction. To use another Nine Inch Nails analogy, take the song "Hurt" (or the Johnny Cash version--both excel for the exact same reason). The musical is small and understated because the lyrics are dark and brooding and if "Hurt" had a three minute guitar solo, it wouldn't make any sense. At the same time, "Closer" lacks introspection but instead is built upon stark drum machine and keyboard sounds. Without the music to compliment its often vulgar and uncomfortable lyrics, "Closer" would have been inclined to scare off listeners. With the music, it works. And likewise, "Kiss" isn't a sonnet but it isn't supposed to be. And its music matches its lyrics. Even a clever quip like "Act your age, not your shoe size" isn't overbearing: It settles in so nicely with the music that you can probably hear the song and most of the time, not consider how dated its reference to the TV series Dynasty is.
"Kiss" is pop perfection because it is everything. Every style, every sentiment, everything that can be great about pop music is incorporated. It's a song that would've been worthy of any of the great rock and roll showmen in history but was best placed in the worthy hands of one Prince Rogers Nelson.