As a developer, DO never looked anything like it. Linode was expensive and on the same playfield as Rackspace and a ton of other cloud hosts, very different from the instantly-spin-up-a-tiny-vm-for-five-bucks model. Their web UI also has always been miles ahead.
The competition also didn’t have SSD as an option until much later, and that was a HUGE selling point for digital ocean at the time.
The UI, the simplicity, SSDs, additional block storage... but also the API and its doc, as well as IPv6, regions, snapshots/backups, and availability. Later on, load balancers, object storage and k8s. All of that much simpler than AWS and both better thought out and more featureful than Linode or OVH.
DO truly deserved their success.
Remember we are talking about early days of DO. Of course later DO innovate more and Linode had to follow. And the new Linode UI is arguably better than DO. Although it did took them years to make it. The beauty of competition.
But the thing I liked best was their "no hidden cost". You pay what you agreed before to pay. No surprise. No upsell, trick sell which were common with all hosting at that time.
DO still maintains that honesty. Not sure what will happen after their IPO.
I'd strongly disagree (been on DO since about 2012 and on Linode a few years earlier; I still use both). DO UI is ok these days but years ago Linode UI was far better in every way.
Linode and Slicehost were very similar stories, though. Slicehost bootstrapped as well and was run by good people.