There can be as much value in the blink of an eye as in months of rational analysis.
Malcolm GladwellThe 10,000-hours rule says that if you look at any kind of cognitively complex field, from playing chess to being a neurosurgeon, we see this incredibly consistent pattern that you cannot be good at that unless you practice for 10,000 hours, which is roughly ten years, if you think about four hours a day.
Malcolm Gladwell