I can say that I like a challenge and you tell me it's painless
You don't know what pain is

from Kendrick Lamar – Bitch, Don't Kill My Vibe Lyrics on Rap Genius

Meaning

The “challenge” Kendrick means could be getting through to these empty-souled people and giving them a message. It’s difficult to try to make people listen deep into music these days but Kendrick is willing to try.

The word “painless” holds the meaning here:

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