The reality is the Lean Startup method is not about cost, it is about speed. Lean startups waste less money, because they use a disciplined approach to testing new products and ideas.
HubSpot has used the lean startup method to build a spectacularly successful company. What I particularly love about HubSpot is that they are so geeked out on data analysis and making evidence-based decisions, which are at the heart of the Lean Startup process.
This is one of the most important lessons of the scientific method: if you cannot fail, you cannot learn.
The lean startup method is not about cost, it is about speed.