A rapper gets paid to rap, a person that raps will do it just because they know how and not for making a living.
Most aspiring artist and rappers really don’t understand exactly what it takes to succeed. For instance most rappers “sleep late”, you gotta get up no later than 9:00am every morning regardless of how late you might have went to bed the night before. Second, a lot of rappers get in the habit of wanting everything done for them and figure all they need to do is rap. You got to understand that its a a lot more to being a rapper than simply writing and recording.
Finally, plenty rappers tend to make music for themselves and not for the public. It doesn’t matter how good you personally think your record is, what matter is can you sell it.