hah i felt the same way. I remember when the Sky Crane was used to put Curiosity down on Mars, I thought there's just no freaking way that's going to work but they pulled it off. When SpaceX started talking about landing boosters I shook my head again but then they did it. The older I get the more blown away (and humbled) I am at what people are capable of achieving.

On a lighter note there's a Simpons line when Homer has to land a plane and is talking to someone on the ground

Colby: Okay Homer, I don't know anything about planes, but I know about you. You have what made America great: no understanding of the limits of your power and a complete lack of concern for what anyone thinks of you. So you'll land that plane. And do you know why? Because I heard some guy say you couldn't.

Homer: What! I'll show him. I'll show that guy!

The best way to get something great done is to tell someone it's impossible for them to achieve.