Most people look for ways to increase their productivity. Many of them believe that they will be more productive by handling several tasks simultaneously, what is known as “multitasking”. But this is actually a trap! By trying to perform many tasks in parallel we just lose our focus and reduce the quality of our work. To be more productive we should actually avoid multitasking!
Effective Software Design 
multitasking only works for tasks that don’t require long hour attention such as management job and some admin tasks.