Some people look at things, especially hard things, and immediately respond "Oh my god, that's impossible, you're crazy" and walk away.
Other people have the ability to look at exactly the same hard things and will momentarily pause, then respond with a thoughtful "Hmm... Sounds crazy. But ya' know... if we just think about it for a minute..."
Old saying (I don't know the source):
"Those who say something cannot be done should not interrupt those actually doing it".