I think you become an expert when you go from "unconscious competence" to "passionate competence" i.e. you care so much about it that you live it, dream it and

I think you become an expert when you go from "unconscious competence" to "passionate competence" i.e. you care so much about it that you live it, dream it and think of it every second. Examples are: * Rand Fishkin and his love of SEO * Jonny Ive and his passion for design * Tony Hsieh and his love of fostering an awesome place to work. All of these people live and love their chosen area of expertise.