Companies go with Juniper because they can outfit a data center at half the price of Cisco. NYSE did that a decade or more ago with their Mahwah data center.
Its not really a bad strategy. If you're going to have a large team of network engineers work continuously on a the Juniper tech stack, they'll get use to it - even if they were raised on Cisco IOS. Juniper stuff works just as well as the rest of them.
For a very long time, Juniper lead over Cisco for performance and features. After the run of the original Catalyst switches, Cisco was floundering, resting on their past successes without really pushing anything.
We bought Juniper gear at the time because nothing Cisco had would work well for us. At least at not any sane price point, and lots of restrictions/gotchas.
Cisco finally got their wind back eventually on their Nexus gear, catching up and run neck-and-neck between Juniper & Arista now.
The first time i did a commit, knocked myself off the system, and it automatically rolled back its config 5 min later because I didn't do a 'commit confirm' was kind of mindblowing.
But Arista only has switching hardware and a few other specialty devices (L1 switches from their Metamako purchase). Vendors like Juniper offer load balancers, firewalls and everything else you need for managing a data center or company.
True, but a lot of companies want to source it all from a single vendor so they can talk to one entity when dealing with configuration/integration issues. Its not how I roll but it is how a lot of big companies operate.
Its not really a bad strategy. If you're going to have a large team of network engineers work continuously on a the Juniper tech stack, they'll get use to it - even if they were raised on Cisco IOS. Juniper stuff works just as well as the rest of them.