Some people will look at a glass of water and say, "It's half full". Some will look and say, "It's half empty". I like to pull out my magnifying glass and ruler and get my eyeballs right up there to look really, really close and determine with precision. Who knows, it could be exactly halfway. Maybe some people don't mind just blurting out guesses, but I prefer not being regarded as an inaccurate nitwit.