What do you mean by "build a prototype and throw it away", exactly? I'm having trouble discerning the meaning behind the image.
https://en.wikipedia.org/wiki/The_Mythical_Man-Month#The_pil...
The lesson is basically, when you're designing a new system or product - make one with the knowledge that you're going to scrap and it start over. The value in doing so is that you expose flaws and design challenges that you can't anticipate through the speculation that occurs before you've actually started.