You seem to be thinking these are contradictory things. In fact, they are complementary. The payment depends both on value (of course, that's subjective, market-driven, influenced by fashions and passions, insert all disclaimers here) and on negotiation skill. If you're a fresh intern knowing next to nothing, no negotiating skill would give you the position of a senior architect with accompanying salary. Bad negotiating skills though can harm you, even though extreme lowballing is dangerous for the employer too - people know what are general salary levels and if you lowball to the extreme, they'd get pissed off and leave for better pastures in exactly the worst moment. Because other employers have interest in high-value people too (or even in cheap moderate-value people).