I can try to answer for US.

We're small (< 25 people). We maintained a single rack in a colo, and all the servers were showing their age. We weighed lease cost for replacement (along with hassle of actually doing it), and migrated into AWS last January.

It's been ... messy. I'm not certain we'll stay. It's easier in the sense that we can bring up arbitrarily many new machines without needing to call Dell when a host gets full, but it's definitely not cheaper. And weirdball AWS-only things get in the way. Oh, and literally nothing is simple or easy in administration or setup.

If I had it to do over again, I think I'd have bitten the bullet and leased more boxes instead.