# Overview
There are many reasons a contact might not be able to be processed, and thus are not sent a message or sent to a channel. Flow Delivery Metrics provides a report of the number of contacts that were not processed when attempting to execute a flow. In Flow Delivery Metrics, contacts are classified by the reason a message wasunable to be sent.
Detailed reasons that contacts were not processed are only displayed if at least one contact was not able to be processed.
Flow Delivery Metrics are displayed on the "Delivery" tab of a flow.
If a flow has variants, metrics are also displayed for each variant.

# Metrics
Column Title | Description |
Total | The total number of contacts evaluated by the flow. |
Not Processed | The total number of contacts that were not sent to the channel for message delivery. |
< Reason of Message Not Processed > | _Number:_ Total number of contacts not processed for a given reason _Percent:_ The percentage of all contacts not processed that were caused by this reason |
# Reasons That Messages Are Not Processed
Reason | Description |
Content failure | There was an error in the content that prevented it from being sent. |
Content not available | The content was not available to send to the contact. |
Device not active | The customers device is no longer active and therefore the push notification didn't go through. |
jinja skip_action() called | The contact was not processed because the contact met the conditions in the skip_action() function that was called within the message. |
Frequency cap | The contact has met the maximum number of messages within the allotted time period. |
Manual Skip | An error occurred with the contact and was skipped in order to complete the flow. |
No **contact** info | The contact has no information to be contacted via this channel. |
Not deliverable to channel | The message or data is unable to be sent to the channel for delivery. |
Not subscribed | The contact is not subscribed to receive messages from this channel. _Not available for SendGrid_. |
User Not Found | We tried to send to the contact, but the contact does not exist in the channel. |
# Supported Channels
Simon Mail
SendGrid
Responsys
SailThru
## Push Notifications
Amazon SNS
Airship
## SMS
Twilio
## Print and Mail
Lob
# Supported Flow Types
Flow Type | Supported |
One-time | ✅ |
Triggered | ✅ |
Stream | ❌ |
Recurring | ✅ |
# FAQ
**_Why is the "total" for a variant different than numbers displayed for SendGrid Engagement Metrics?_**
SendGrid Engagement Metrics shows the number of "Sent" messages. This numbers includes unsubscribed contacts.
Unsubscribed contacts are not represented in Flow Delivery Metrics for SendGrid.
The difference between the numbers equals the number of contacts in the segment that were unsubscribed at the start of the flow.