Some times the sides of a data cabinet is blocked with cables. So side-to-side airflow is no longer a "norm". This gets worst when you have a rack-full of servers with front to back airflow.
What we had is get our nexus attacked facing the back so it will be in the same side facing the ethernet cables of servers. All our Nexus have back to front airflow, i. e. hot airflow is being ejected out the front where the interfaces are.
