diff --git a/pkg/source/pubsub/pubsub_source.go b/pkg/source/pubsub/pubsub_source.go
index 91af3c8f..adedd826 100644
--- a/pkg/source/pubsub/pubsub_source.go
+++ b/pkg/source/pubsub/pubsub_source.go
@@ -171,7 +171,7 @@ func (ps *pubSubSource) Read(sf *sourceiface.SourceFunctions) error {
 
 	sub := ps.client.Subscription(ps.subscriptionID)
 	sub.ReceiveSettings.NumGoroutines = ps.streamingPullGoRoutines         // This sets the number of goroutines that can open a streaming pull at once
-	sub.ReceiveSettings.MaxOutstandingMessages = ps.maxOutstandingMessages // maxOutstandingMessages limits the number of messages processed at once
+	sub.ReceiveSettings.MaxOutstandingMessages = ps.maxOutstandingMessages // maxOutstandingMessages limits the number of messages processed at once (each spawns a goroutine)
 	sub.ReceiveSettings.MaxOutstandingBytes = ps.maxOutstandingBytes
 	sub.ReceiveSettings.MinExtensionPeriod = time.Duration(ps.minExtensionPeriodSeconds) * time.Second