Not considering Infrastructure as Code (IaC) for environment setup
Setting up the environment is an essential activity to be carried out to deploy any application. Many companies have strategies for creating multiple environments, such as staging, canary, and production to help deploy their workloads for testing and going live. Infrastructure as Code (IaC) provides a platform for creating the script for your infrastructure and deploying it to as many environments as necessary. Imagine that you manually set up an infrastructure that takes 5 days to complete for a single environment, while replicating it for other UATs, staging, and performing a canary deployment needs an additional 15 days. Moreover, if any part of the environment crashes, resetting would take the same time again. With IaC, since the whole configuration is written in the form of a script, you can deploy in minutes and easily replicate to multiple environments.
Azure Resource Manager (ARM), from Microsoft, and Terraform...