Because it helps you understand the level of cognitive processes involved in human learning, that is the natural order according to which your target audience will process the information you present. (elearningindustry.com)
The development of social cognitive processes in infants and children has also been researched extensively (see developmental psychology). (en.wikipedia.org)
Knowing the order that cognitive processes involved in learning take place, will significantly help you set your learning objectives accordingly. (elearningindustry.com)