lineage qualifications

[Tegridy Reef]

so I'm a little confused on the term linage. It's probably the most asked question when buying a frag. But other then buying directly from that person it's kind of heard to prove. I realize some corals are common so finding lineage is easy. But for instance I saw a person post for a coral Id. The people committed with what they thought it was and some disagreed with them so it was not an annomoius conclusion. Then the person sold with this super high end name and wasn't proven or have a connection of what actually is. So what's every ones thought on lineage. I also fell like some corals might have two names. I fell like if you don't have a firm proof they should rename it but can't sell for what they think it is.