Open office plans became popular in the last ten years with the idea to help productivity. However, this plan is not as beneficial as it was first thought. Half of the people in the world are introverts; and the more open an office plan, the more it will hurt half the employees in the company. Introverts need individual, quiet space in order to work most efficiently, and open office plans offer no protection for introverts.
In fact, although open office plans may allow extroverts to talk to each other more easily (talking over introverts in the process), some studies have shown that productivity has gone down for both personality types.