Lets do some more examples to help:
If you have a network marketing opportunity, finding other network marketers who already believe in network marketing is easier than selling someone who doesn't know about it on the idea. They are also most likely to stay and be able to handle rejection the typical new person can't So you would target other companies in your targeting (not to big like Amway), or people who sell Network Marketing coaching/training.
What if you sell golf gear? Would you target Tiger woods or Big competitions? No, people who watch it may not all play it, but most of them who play it, watch it. You would want to target other golf GEAR brand names. Example, I don't play golf, I have no idea what brands of clubs there are, or golf gloves, etc. But I know Tiger Woods, I know the PGA, I even enjoy watching it from time to time. But your ad would be wasted on me if you targeted those.
I hope this help makes breaking down the layers of targeting better. This strategy has allowed me to maintain 3x-15x ROI's for clients and works best for interest targeting, not keyword targeting. You would use the same method, but target more direct keywords, further than you can with interests, but we will save that for another day!
Have a great day!