Kevin is the sous chef at a local restaurant. He calls the staff meeting to order. Before Kevin can begin the business, the restaurant owner comes in and starts to speak, agitatedly.
"I want to change how we work. Starting tomorrow, I want all of the waiters to report to work at 6am. Then, they will contact all of the customers that are coming to our restaurant and get their orders. We'll write all of those up, and then get them to confirm them with a credit card. Then, the kitchen staff will cook all of the meals for the day. When the customers arrive, the waiters will seat them and bring them their meals! Think of how efficient that will make us! Think of how pleased the customers will be when they get their food so quickly! And we'll charge their credit cards sooner and get more money!"
Kevin stares at the owner, and two mini-Kevins pop up, one on each shoulder.
"Kevin! He's insane! How will you predict who's coming? How will you keep the food warm? What if they change their minds? What if..."
The other mini-Kevin interrupts. "Bah! Keep your mouth shut, Kevin, this is your chance to move up... hee hee..."
Kevin's eyes cut left and right quickly, struggling on what to do?
"Uhm, boss, may I say something?" asks Kevin.
"Eh? Yea, sure."
"Well, we're pretty efficient already. We prepare in advance only what we need, and only those ingredients that take a lot of time to prepare, like our sauces. We cut and prepare our bulk so that we can react quickly, but we keep it to a minimum to preserve our workspace and freshness. And, well, our customers get drinks, appetizers, bread, etc., all within a few minutes of being seated.
We don't start cooking their meal until they decide what they want and place an order..."
I submit the modern, well-run commercial kitchen is Lean. Furthermore, it is a better analogy for building software in these, the Aughts.