The difference between agile and lean is simple to understand, but most people feel they are somehow equivalent.
They are not.
Lean — is designed to reduce waste and improve operational efficiency, especially related to repetitive tasks as often in seen in manufacturing.
Agile — is designed to execute tasks over a short time frame, with frequent customer involvement, and to be able to make changes quickly.
As you can see they have nothing to do with each other per se — one doesn’t need to be innovating new product to be lean, and one doesn’t have to be operationally efficient to be agile.
So why the confusion? One reason is that many people don’t understand the difference.
The larger reasons for the confusion is the vendors see both “Lean” and “Agile” as hot buttons and so they all say their method does both. “Scrum is Lean” shrieks Jeff Sutherland. “Lean is Agile” shriek the kanban vendors.
They themselves dilute the meaning of their own value propositions such as they exist.
They use a logical fallacy — that if A is “good” and B is “good” then A and B are equal and interchangable!
They are not — apples and oranges are still different, even if they both are useful.
Finally, it’s worth noting, that companies that revolve around operational efficiency (pumping out cheaper clones of competitors products) don’t last very long in the marketplace.
What works in manufacturing may not be appropriate for software development.
“Lean Startup” may in fact try to combine elements of both, but that doesn’t make Agile inherently Lean nor vice versa.
I question the validity of the “Minimally Viable Product” in any case — they are of the opinion that if you get there first you will own the marketplace.
Lots of people got there before youtube, lots of people got there before google and lots of people got there before facebook (myspace anyone?).
People need to understand and choose what to optimize for in their unique context, not just grab off the shelf buzzwords that other people fancy.
It would seem that marketplace is voting for the superior product, not the one that got there the cheapest (lean) or quickest (agile).