I walked into the worlds largest camera shop in NYC thinking I knew what I wanted to buy.  Robert had been selling binoculars here for who knows how long.  He patiently showed me what I asked for.  Then he asked a few questions.  It became apparent he was extraordinarily knowledgeable about the particular model I asked about;  he knew the guy who designed them.  And he knew their shortcomings.  I thought, “time to be a learner.”

He showed me an alternative, better suited for my purpose and saved me over $500.  I walked out a richer and wiser learner.