
“Someone widely recognised as a reliable source of technique or skill whose faculty for judging or deciding rightly, justly, or wisely is accorded authority and status by their peers or the public in a specific well distinguished domain. An expert, more generally, is a person with extensive knowledge or ability in a particular area of study.”
Dominating a sector is also extremely cost-effective and we are far better committing all our time, energy and money to a specific target, than trying to accommodate everyone in that sector.