In the time of lean management and business models, is it that essential for startups to have business plans?

Without question it would be close to useless to expect any kind of profit / success in the market without an actual plan.

Dear Mohammad,

Business Plan is like a blueprint of the business setup and any business need it. its like making clear boundaries and defining responsibilities for every stake holders, 

We do not play Buzkashi, rather we play soccer which is quite well defined team work.

my best