Have you seen companies that run like clockwork? Very efficient (Lean) — doing things right. I bet you have seen such companies.
Too efficient, however; the practices that made them very efficient directly limited their ability to adapt and to innovate. Why change a perfectly good and efficient model? Just keep making more of the same! Right?
Then came along the innovators; the disruptors of status quo.
Suddenly, the efficient companies have a problem…it is not an efficiency problem; they have an adaptability problem.

What are those companies that failed or were too late to adapt? Book industry: Borders (gone), Amazon (in); Technology industry: Blackberry (gone), iPhone (in) ; Yahoo (gone), Google (in); Other industries: Blockbuster (gone), Netflix and RedBox (in); Taxi (gone), Uber (in)… you get my drift.
To survive in this day and age, it pays to be Efficient (Lean) and Effective (Agile/Adaptive).