SharePoint 2010 error when trying to delete a managed account: An object in the SharePoint administrative framework, SPManagedAccount Name=managed-account could not be deleted because other objects depend on it. Update all of these dependants to point to null or different objects and retry this operation.

After deleting a Service Application, you may want to clear up the corresponding managed account that you created for the Service Application.

You may run into this error when attempting to delete the managed account in SharePoint Central Administration:

An object in the SharePoint administrative framework, SPManagedAccount Name=managed-account could not be deleted because other objects depend on it.  Update all of these dependants to point to null or different objects and retry this operation.

Solution:

Remove the dependency, which is a Service Application Pool that may depend on this managed account.
Get-SPServiceApplicationPool (to get a list of the Application Pools, you will need to take note of the name for the next powershell cmdlet).
Remove-SPServiceApplicationPool (then enter the name of the Application Pool). Remove the Managed account via Powershell or through the GUI
Get-SPManagedAccount
Remove-SPManagedAccount