The problem with prototypes
"This is just a sketch."
"...a rough draft..."
"...something we threw together..."
I'm a huge fan of prototyping. Prototyping just about anything is faster and more effective than ever before. It makes hypothetical questions go away and surfaces real issues. It gets things moving. And most important of all, prototyping eliminates fear.
If you use a prototype to try to persuade someone of an idea, be careful. Most people you know are not as conceptual as you are, especially about stuff you really care about. The first prototypes for an iPod or a book cover or a Starbucks or a six-year public works construction project certainly did not impress the outsiders who saw them.
Too many times, I've gotten excited about an idea and created a conceptual prototype. And almost every time, people, smart people, didn't get it.
Here's my new prototype rule of thumb: your prototype has to be better (better build quality, faster interface, better lighting, whatever) than the finished product is going to be. That's what people expect anyway--they see your prototype and take off 20% for reality.