diff --git a/superset/models/alerts.py b/superset/models/alerts.py
index b61baefab52ca..95e7c06042d90 100644
--- a/superset/models/alerts.py
+++ b/superset/models/alerts.py
@@ -203,7 +203,7 @@ def alert(self) -> RelationshipProperty:
             backref=backref("validators", cascade="all, delete-orphan"),
         )
 
-    def __str__(self) -> str:
+    def pretty_print(self) -> str:
         """ String representing the comparison that will trigger a validator """
         config = json.loads(self.config)
 
diff --git a/superset/tasks/schedules.py b/superset/tasks/schedules.py
index 94808a8e21dc0..d1fabc9f3e6d4 100644
--- a/superset/tasks/schedules.py
+++ b/superset/tasks/schedules.py
@@ -105,7 +105,7 @@ class AlertContent(NamedTuple):
     label: str  # alert name
     sql: str  # sql statement for alert
     observation_value: str  # value from observation that triggered the alert
-    validation_str: str  # a string of the comparison that triggered an alert
+    validation_error_message: str  # a string of the comparison that triggered an alert
     alert_url: str  # url to alert details
     image_data: Optional[ScreenshotData]  # data for the alert screenshot
 
@@ -575,8 +575,8 @@ def deliver_alert(
     # where an alert might not have a validator
     recipients = recipients or alert.recipients
     slack_channel = slack_channel or alert.slack_channel
-    validation_str = (
-        str(alert.observations[-1].value) + " " + str(alert.validators[0])
+    validation_error_message = (
+        str(alert.observations[-1].value) + " " + alert.validators[0].pretty_print()
         if alert.validators
         else ""
     )
@@ -586,7 +586,7 @@ def deliver_alert(
             alert.label,
             alert.sql_observer[0].sql,
             str(alert.observations[-1].value),
-            validation_str,
+            validation_error_message,
             _get_url_path("AlertModelView.show", user_friendly=True, pk=alert_id),
             _get_slice_screenshot(alert.slice.id),
         )
@@ -596,7 +596,7 @@ def deliver_alert(
             alert.label,
             alert.sql_observer[0].sql,
             str(alert.observations[-1].value),
-            validation_str,
+            validation_error_message,
             _get_url_path("AlertModelView.show", user_friendly=True, pk=alert_id),
             None,
         )
@@ -626,7 +626,7 @@ def deliver_email_alert(alert_content: AlertContent, recipients: str) -> None:
         label=alert_content.label,
         sql=alert_content.sql,
         observation_value=alert_content.observation_value,
-        validation_str=alert_content.validation_str,
+        validation_error_message=alert_content.validation_error_message,
         image_url=image_url,
     )
 
@@ -645,7 +645,7 @@ def deliver_slack_alert(alert_content: AlertContent, slack_channel: str) -> None
             label=alert_content.label,
             sql=alert_content.sql,
             observation_value=alert_content.observation_value,
-            validation_str=alert_content.validation_str,
+            validation_error_message=alert_content.validation_error_message,
             url=alert_content.image_data.url,
             alert_url=alert_content.alert_url,
         )
@@ -656,7 +656,7 @@ def deliver_slack_alert(alert_content: AlertContent, slack_channel: str) -> None
             label=alert_content.label,
             sql=alert_content.sql,
             observation_value=alert_content.observation_value,
-            validation_str=alert_content.validation_str,
+            validation_error_message=alert_content.validation_error_message,
             alert_url=alert_content.alert_url,
         )
 
diff --git a/superset/templates/email/alert.txt b/superset/templates/email/alert.txt
index 1e823ae977bac..964a57e3ccef2 100644
--- a/superset/templates/email/alert.txt
+++ b/superset/templates/email/alert.txt
@@ -20,7 +20,7 @@
 <p><b>Query:</b></p>
 <code><mark style="background-color: LightGrey; font-size: 1.1em">{{sql}}</mark></code></p>
 <p><b>Result</b>: {{observation_value}}</p>
-<p><b>Reason</b>: {{validation_str}}</p>
+<p><b>Reason</b>: {{validation_error_message}}</p>
 <p><a href="{{alert_url}}">View Alert Details</a></p>
 <p>Click <a href="{{image_url}}">here</a> or the image below to view the chart related to this alert.</p>
 <a href="{{image_url}}">
diff --git a/superset/templates/slack/alert.txt b/superset/templates/slack/alert.txt
index 223c7f965b7c4..df943f5ef090e 100644
--- a/superset/templates/slack/alert.txt
+++ b/superset/templates/slack/alert.txt
@@ -19,6 +19,6 @@
 *Triggered Alert: {{label}} :redalert:*
 *Query*:```{{sql}}```
 *Result*: {{observation_value}}
-*Reason*: {{validation_str}}
+*Reason*: {{validation_error_message}}
 <{{alert_url}}|View Alert Details>
 <{{url}}|*Explore in Superset*>
diff --git a/superset/templates/slack/alert_no_screenshot.txt b/superset/templates/slack/alert_no_screenshot.txt
index fd48da94aa71d..bca191bb035a2 100644
--- a/superset/templates/slack/alert_no_screenshot.txt
+++ b/superset/templates/slack/alert_no_screenshot.txt
@@ -19,5 +19,5 @@
 *Triggered Alert: {{label}} :redalert:*
 *Query*:```{{sql}}```
 *Result*: {{observation_value}}
-*Reason*: {{validation_str}}
+*Reason*: {{validation_error_message}}
 <{{alert_url}}|View Alert Details>
diff --git a/tests/alerts_tests.py b/tests/alerts_tests.py
index 5659447b75a9e..a2226107a01d8 100644
--- a/tests/alerts_tests.py
+++ b/tests/alerts_tests.py
@@ -330,7 +330,7 @@ def test_deliver_alert_screenshot(
         "initial_comment": f"\n*Triggered Alert: {alert.label} :redalert:*\n"
         f"*Query*:```{alert.sql_observer[0].sql}```\n"
         f"*Result*: {alert.observations[-1].value}\n"
-        f"*Reason*: {alert.observations[-1].value} {str(alert.validators[0])}\n"
+        f"*Reason*: {alert.observations[-1].value} {alert.validators[0].pretty_print()}\n"
         f"<http://0.0.0.0:8080/alert/show/{alert.id}"
         f"|View Alert Details>\n<http://0.0.0.0:8080/superset/slice/{alert.slice_id}/"
         "|*Explore in Superset*>",