With 40 acquisitions & counting.. Palo Alto Networks CEO Nikesh Arora (@nikesharora) shares the biggest mistake people make during acquisitions: "They underestimate the intelligence of the people who built the business that you acquired." "Sometimes people take on the imperialistic attitude, 'I bought you, hence you must work for me.'" "Our attitude is, 'You kicked our ass. Come tell us what we did wrong.'" "We spend our time trying to understand what they figured out, find a way that we…