To be honest, I can't really think of anything. I have to hear more than one good song from an artist to be a fan. Like I can hear a song with an open mind and want to an artist, but they have to be able to deliver consistent quality for me to be a fan.
For example, I heard this:
and decided to check Wiz out. After listening to Kush and OJ, I decided he was ok, but his subject matter was way too limited for me to be a fan.
On the flip side, I heard this:
and had to check out Kendrick. I listened to Good Kid Mad City and was hooked on his music after that.