All the power, ultimately, lies with the sub.
Iif the sub doesn't accept me as a dom, I can't dominate her. If she doesnt accept my authority, I can't tell her what to do. If the sub simply refuses to submit, then I am at a loss.
The sub needs to accept my authority over her and the power of my decree has to compel her on some level. Nothing I do can force that. All that comes about by her conscious or unconscious will.
Sure, a good, experienced dom will likely have developed talents and skills such as physical presence, strength of personality, charisma and gravitas that make his acceptance easier to the sub. But nothing the dom does can mystically force another person - however they are naturally inclined - to submit.
This is why getting to know your sub before any kink matters. This is why being a dom is not just rough sex and a telling off voice. A good D/s relationship is a reciprocal thing. The sub gives the dom at least as much as the dom gives the sub.
Earn your sub's trust and she will tell you all the things that turn her on. She will show you how she prefers to be dommed - cos that matters just as much as your domming style. The clue is in the term "relationship". It exists for both parties.