Quote Originally Posted by Q.G. View Post
The answer is extremely simple: because we suck at it. Big time.
That's why we have invented meters, that (though you perhaps can't manage to make them work for you) are infinitely better.
That's why.
A light meter isn't a pocket calculator you can't just accept the answer given, it's more like a slide rule it requires some skill and interpetation to arrive at the right answer.