Ultimately, someone comes to a search engine with a need. The search engine's top priority is to satisfy that need. That's the relationship that matters to the search engine. That's the customer. Supplying you visits is not what the search engine cares about. Your source site is a means. It's not the ends.
Your website page rank, and such are effectively irrelevant. The priority isn't you. It's the asker. They have the need. They need to be happiest.
Yes. Of course. There are things you can do help the search engine help others. The key to maximum effectiveness is to understand your role and your place in the process.