ARM and ASM

ASM has inherent constraints and some of the major ones are discussed here: ASM deployments are slow and blocking. Operations are blocked if an earlier operation is already in progress:

• Parallelism: Parallelism is a challenge in ASM. It is not possible to execute multiple transactions successfully in parallel. The operations in ASM are linear and executed one after another. Either there are parallel operation errors or they will get blocked.
• Resources: Resources in ASM are provisioned and managed in isolation from each other, there is no relation between ASM resources. Grouping of services and resources or configuring them together is not possible.
• Cloud services: Cloud services are the unit of deployment in ASM. They are reliant on affinity groups and not scalable due to its design and architecture.

Granular and discreet roles and permissions cannot be assigned to resources in ASM. Users are either service administrators or co-administrators in the subscription. They either get full control on resources or do not have access to them at all. ASM provides no deployment support. Deployments are either manual or you will need to resort to writing procedural scripts in PowerShell or .NET.

ASM APIs were not consistent between resources.