Occasionally, there are laws that also mandate certain controls that cloud providers in general did not have. That is also becoming rarer as time goes on.
There are cons, don't get me wrong, but to somehow claim that AWS is the end all be all of hosting choices is demonstrably wrong.
For example - You want to develop a financial exchange with a 100 microsecond average response time, peaks of 10Gbit traffic, and 5 9s of uptime. Do you host that on AWS? I wouldn't.
Another example - If I were a medium+ sized company (say 20+ employees), I would want my source control 100% on prem (excluding backup). Internet connections are too flakey, and Github gets DDOSed too often. I could not stake my entire business on github.
a) have a very competent dev and ops team b) have a business where you are the provider of an SLA.
For many companies with 5K+ employees, they are already distributed, already have multiple data centers, have workers all over the globe, and, when they are not primarily in the IT delivery business, tend to have IT departments that have limited budgets, lack of training and poor organizational awareness.
This leads to poor security practice, poor cost analysis, and long/nonexistent upgrade cycles on many behind-the-scenes workloads.
You are of course right, there are many diverse reasons to be on-prem, but at some point, many of those reasons go away with sufficient size and differing priorities. Things change when a company's business involves the consumption of IT services, rather than the delivery of IT services.
I can understand why on-premises git is better in some ways.
But you're overstating the frequency of github outages.
And it doesn't exactly kill the business when it's down for an hour.
Git is distributed after all.
It's a little of topic, but I don't think it's overstated. People complain about the stability of something like HipChat all the time, but GitHub is unavailable more often, in our area at least.
GitHub is huge target, and outages are extremely disruptive for companies.
It's not the primary reason for On Premises, but it's one less thing to worry about: "our tech team has full control, instead of yet another company having some control that we can't see"
