What Makes a Song Iconic?

Iconic isn't the same as good. It isn't the same as popular. It isn't even the same as influential.

A song is iconic when it stops belonging to its listeners and starts belonging to the culture.

Four quick tests. A song needs two or three:

Recognition — You know it in two seconds. The riff, the drum fill, the first line. Even if you weren't born yet.
Reach — It's escaped the record. Stadiums, memes, ads, protests, karaoke, funerals. The culture uses it.
Impact — Something changed after it. A genre broke through, a barrier fell, the sound of music shifted.
Staying Power — It still works decades later, for people with no nostalgia riding on it.

Now: Play it, queue it, or skip it.