2. Lack of support. There is a general lack of binaries already compiled for ARM. Photoshop? Visual Studio? etc
The story behind ScaleWay
"We underestimated the lack of upstream kernel support with our new hardware. The SoC we were using, was usually employed in NAS servers and mobile phones, which only need stability and performance, so they don’t care about having a closed-source patched kernel, but our users do."
https://medium.com/scaleway-cloud/thank-you-scaleway-9dc5ba30b9a5#.jy9ubokpu
In fact, those 3€ ARM servers are near useless, and slow at best, if you want to develop systems..