It can be said that YARN is a boon to the big data industry. Without YARN the entire big data industry would have been at serious risk. As the industry started playing with big data, new and emerging varieties of problems came into the picture and hence new frameworks.

YARN's support to run these new and emerging frameworks allows these frameworks to focus on solving the problems for which they were specifically meant for, while YARN takes care of resource management and other necessary things (resource allocation, scheduling jobs, fault tolerance, and so on).

Had there been no YARN, these frameworks would have had to do all the resource-management on their own. There are many big data projects that failed in the past due to unrealistic expectations on immature technologies.

YARN is the enabler for porting mature and enterprise-class technologies directly onto Hadoop. Without YARN, the only thing in Hadoop was to use MapReduce.