DevOps and corporations

DevOps fits perfectly into the small company world (start-ups): some individuals that can access everything and execute the commands that they need to make the changes in the system quickly. Within these ecosystems is where DevOps shines.

This level of access in traditional development models in big companies is a no-go. It can be an impediment even at a legal level if your system is dealing with highly confidential data, where you need to get your employees security clearance from the government in order to grant them access to the data.

It can also be convenient for the company to keep a traditional development team that delivers products to a group of engineers that runs it but works closely with the developers so that the communication is not an issue.

SREs also use DevOps tools, but usually, they focus more on building and running a middleware cluster (Kubernetes, Docker Swarm, and so on) that provides uniformity and a common language for the developers to be abstracted from the infrastructure: they don't even need to know in which hardware the cluster is deployed; they just need to create the descriptors for the applications that they will deploy (the developers) in the cluster in an access-controlled and automated manner in a way that the security policies are followed up.

SRE is a discipline on its own, and Google has published a free ebook about it, which can be found at https://landing.google.com/sre/book.html.

I would recommend that you read it as it is a fairly interesting point of view.