There are more than 1 pricing strategies and they depend on the market. You can have standard/set markups (nominal or %), small margins but high volume (tightly coupled to cost), set prices based on features/brand/luxury (decoupled from costs)...

I think most people would rather sell their goods with a defined profit margin (1), because if they can drop manufacturing costs, their prices will come down but they'll likely sell more.

2 is fine for monopolies (from a sales perspective).

3 is better suited to luxury goods.