Why is anything else a waste and what companies started focusing on customers first (give two examples)?

From LS Chapter 3

True startup productivity: systematically figuring out the right things to build. In the lean
startup, every product, every feature, every marketing campaign – everything a startup does
– is understood to be an experiment designed to achieve validated learning.

Lean thinking: Lean thinking defines value as providing benefit to the customer, anything
else is waste.

Why is anything else a waste and what companies started focusing on customers first (give two examples)?

Impact Is The New Mobile | TechCrunch

Are You Running A Startup Or Small Business? What’s The Difference? (forbes.com)

In Chapter 5 & 6 from WIW

After all, that’s “The Secret Sauce of Silicon Valley” (Chapter 5): a failing forward resumeLinks to an external site..

In the sixth chapter – “No Way… Engineering is for Girls”

Describe each chapter in 5 – 7 sentences

Concept to company: https://venturebeat.com/2020/02/04/from-concept-to… to an external site.

Order of Operations:
https://www.ycombinator.com/library/61-order-of-op… to an external site.
Biggest Mistake First Time Founders Make:
https://www.ycombinator.com/library/66-biggest-mis… to an external site.
How to Start a Blog:
https://www.ryrob.com/how-start-blog/Links to an external site.
Library for Business Research (Module: 45 minutes to 1 hour) available through Canvas.
Writing Center:
https://writingcenter.sdsu.edu/Links to an external site.