Not all music is dance music, although most popular music is danceable. Dance music varies in difficulty so some music is better for dancing than other music, which is, in part, a personal preference. But some music is just not danceable. The jazz music of Count Basie, known as swing, is usually good dance music but the jazz of Miles Davis, known as bee bop, is not dance music at all.
I don’t typically dance every song in an evening of dance so, strategically, I sit out the music that’s not dance music or is music that’ll be difficult for me. This makes me appear to be a better dancer. If you struggle with dance, choose your music wisely.
For me, if I can count sets of 8 and if it makes me feel like dancing and if I can visualize myself doing some steps (that’s when I evaluate if the tempo is too fast), then it’s dance music. If I can’t count sets of 8 I try counting sets of 6 to see if it’s a waltz, although my guess is that less than 2% of popular music is a waltz. If that doesn’t work it probably isn’t dance music or, at least, it’s not good dance music for me.
If I can’t count sets of 8 and it still feels danceable—it’s usually something with a slow tempo–I might try an improvisational slow dance. If that doesn’t work and the song isn’t over, I sometimes let it evolve into a Steve-Martin-esque parody of a slow dance. There’s a classic parody of a “slow fox trot”—not sure what you call it—by Steve Martin and Gilda Ratner from Saturday Night Live. I was going to give the youtube link but the video “is no longer available.” If I ever find it, I’ll post the link.