We use on-premises setups for almost everything (we generally avoid cloud solutions to have full control of our data), sometimes (approximately once a month) it goes down for a few minutes which already feels like a torture because all our processes depend on it, I can't imagine having no access to it for several weeks, all our work would stop to a halt... The office of the guy who administers on-premise servers is l…
Experienced people hosting and tuning Atlassian products has a greater success rate than someone doing it alone for a large company. Almost every time I’ve migrated an old Atlassian installation under our wing it’s given me shock how users have been made to suffer the loading times and perfs that come from underprovisioning (db or actual machine) and messy configuration. I’m not blaming the former admins but it just happens. Usually end users are happy after we clean the mess up and everything feels snappy.
Disclosure: I’ve worked in this kind of expert role.