Apples and oranges: Determining song rankings

As I prepare to rank my favorite songs of 2015 in tomorrow's post, I identify with Rob's plight in the movie High Fidelity as he's ranking his favorite songs for a reporter--and calling her back, asking her to move one song up in the rankings and another one down.  I've approached song rankings that way before, thinking and rethinking them as though the fates of nations were on the line.  Ultimately, a person's favorite songs fall where they do in the rankings because of personal taste and other factors that can't be explained fully.  When I'm ranking a list of favorite songs for the year, though, the following factors typically come into play:

• How does the strong strike me?  What draws me to it?  Is it the tune's well-written, thought-provoking lyrics, well-sung vocals, and/or well-played instrumentation?  Or, does it just have a catchy hook?
• Do I truly like this song, or am I willing it to make my rankings because of my respect for the artist's prior work?
• If it's a live recording of a song the artist has released previously as a studio rendition, does the live version's quality equal or surpass the studio take?  Is it truly a strong live version, or am I letting my opinion of the studio version or the crowd's feedback in the live version cloud my judgment? 
• If it's a cover song, does its quality equal or exceed the original version's quality?  Does the artist bring something new and imaginative to the table, or is it a version that stays as close to the source as possible?  Depending on the song, either approach has its merits.
• How well does the song stand up to repeated listening?  A cerebral singer-songwriter might present a well-argued case in song, for instance, that climate change needs to be taken seriously.  While I might admire the heart and conviction behind the lyrics and might not be able to refute them, the song might not have much of a discernible, memorable melody.  On the flip side, a song might have an extremely catchy hook, but after three or four listens, I've had my fill of it because there's not much there. 
• Am I letting the fact that I first heard this song back in January or February cloud my judgment?  Does the song not seem as fresh to me now because I've heard it so often?  Or, has hearing it so often strengthened my conviction that it's excellent?  If I heard a song for the first time just two weeks ago, am I not giving it its due because it's still fairly new to me?  Or, do I like it because it just hasn't worn out its welcome yet?
• Is my current mood influencing where a song is ranked?  If I'm in an upbeat mood, am I not giving this subtle piano instrumental the credit it deserves?  Or, if I'm in a quiet, reflective mood, am I not acknowledging how good this uptempo track with a blistering guitar melody is?
• How do I rank one song against another when their genres are completely different?  As you may have noticed from reading this blog, I tend to favor singer-songwriter music, jazz, and power pop most often.  When I like two songs almost equally, what breaks the tie in my rankings?  That leads me into my final bullet point.
• Which songs have I listened to most?  I can talk about admiration and respect for a song or an artist all I want, but in the end, it comes down to this: What songs have made me listen to them--not out of any obligation, but simply because I like them?

I'll rank my favorite songs of 2015 in tomorrow's post and include a list of many honorable mentions.  We'll see how it turns out--and if I end up revising my choices later.