Good question! My tagging is very much based on whether I want it to come up in shuffling, so if it's enjoyable enough that I still want to listen to it I'll leave it untagged. ("Africa" and a cover of "Do They Know It's Christmas" are both in this group.) And I have a few ways for something to be removed from shuffle: I have three separate groups, A for songs like "Vincent" by Don McLean, B for songs like "I'm Gonna Love You Just A Little More" by Barry White, and C for songs like "Rose, Rose I Love You" as mentioned above as well as "Brown Sugar." There's also L for language, which isn't removed from shuffling but which I wouldn't necessarily want to come up if I was playing music in public. It got a lot of Billboard songs starting in the late 90s because I am very white.

I'm sometimes surprised by what I tag: both "Love Potion Number 9" by the Searchers and "You're Sixteen" by Ringo Starr are songs I've heard many times and never considered exceptionable, but listening to them last year, I had a negative reaction and tagged them into Not For Shuffle C.