Whilst giving Tim Dodd a tour of a SpaceX facility, Musk described an interesting five-step engineering process:

1. Make the requirements less dumb.

   • The requirements are definitely dumb; it does not matter who gave them to you.
   • Requirements are particularly dangerous if an intelligent person created them, because you may not question them enough.
   • "Everyone’s wrong. No matter who you are, everyone is wrong some of the time."
   • "All designs are wrong, it’s just a matter of how wrong."

2. Try very hard to delete the process or the component.

   • If parts are not being added back into the design at least 10% of the time, not enough parts are being deleted.
   • Musk noted that the bias tends to be very strongly toward “let’s add this part or process step in case we need it.”
   • Each requirement must come from a name, not a department.
   • A department cannot be asked why a requirement exists, but a person can.

3. Simplify and optimize the design. Remove stuff.

   • The most common error for a smart engineer is to optimize something that should not exist.

4. Accelerate cycle time.

   • "You’re moving too slowly, go faster! But don’t go faster until you've worked on the other three things first.”

5. Automate.

   • An important part of this is to remove in-process testing after the problems have been diagnosed;
   • If a product is reaching the end of a production line with a high acceptance rate, there is no need for in-process testing.

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