added notes to failures page

docs/references/failures.mdx

@@ -52,17 +52,16 @@ This is the only type of Temporal Failure created and thrown by user code.
 An error in a Workflow can cause either a **Workflow Task Failure** (the Task will be retried) or a **Workflow Execution Failure** (the Workflow is marked as failed).
 
 Only Workflow exceptions that are Temporal Failures cause the Workflow Execution to fail; all other exceptions cause the Workflow Task to fail and be retried (in Go, any error returned from the Workflow fails the Workflow Execution, and a panic fails the Workflow Task).
-Most types of Temporal Failures are raised by the Temporal Service, rather than the application developer, such as a [Cancelled Failure](#cancelled-failure) when the Workflow is Cancelled or an [Activity Failure](#activity-failure) when an Activity Fails.
+Most types of Temporal Failures are raised by the Temporal Service, like a [Cancelled Failure](#cancelled-failure) when the Workflow is Cancelled or an [Activity Failure](#activity-failure) when an Activity Fails.
 In contrast, the application developer can explicitly fail the Workflow Execution by throwing an Application Failure (returning any error in Go).
 
 #### Workflow Task Failures
 
 A **Workflow Task Failure** is an unexpected situation failing to process a Workflow Task.
-This could be triggered by raising an exception that is not an Application Failure in your Workflow code.
+This could be triggered by a non-Temporal exception being raised (panicking in Go) in your Workflow code.
 Any exception that does not extend Temporal's `FailureError` exception is considered a Workflow Task Failure.
-These types of failures will cause the Workflow Task to be retried.
-
-> what if things extend FailureError, but not ApplicationError??
+These types of failures will cause the Workflow Task to be retried until the
+Workflow Execution Timeout, which is indefinite by default.
 
 #### Workflow Execution Failures