From somewhere in the middle of this article: In the software world we have oft used anecdote: Cost, Scope, Time: pick the two you want, you can't get all three. You roll it out whenever someone asks you to build Amazon.com when they only have a Wordpress level budget or a two week deadline. I like it for its brevity and conciseness, its understood immediately and retained well. It also gives a nice insight into the difficulties of a particular technical domain, yet avoids having to explain anything technical at all. Are there other examples of this in other fields beyond Software and Spycraft? I would assume Politics, Medical practice, Law, Criminal investigation has similar trade-off triangles.One is what I would like to call the communication triangle. Communications can be secure, easy to use or hard to detect. But seldom all three.