After an application is deployed to production, developers should lock down its underlying infrastructure to prevent accidental changes. Some of the common accidents that can affect the availability of an application in production are: moving, renaming, or deleting the resource crucial to the function of the application. You can use locks that prevent anyone from performing a forbidden action to avoid such mishaps.
Almost every resource in Azure supports locks, so you will find the lock option in the settings section of nearly all resources in the portal. For example, the following screenshot illustrates locks on resource groups: