diff --git a/src/receive_imf.rs b/src/receive_imf.rs
index f5f9a0525..012106eef 100644
--- a/src/receive_imf.rs
+++ b/src/receive_imf.rs
@@ -545,8 +545,15 @@ pub(crate) async fn receive_imf_inner(
         if mime_parser.incoming {
             return Ok(None);
         }
-        // For the case if we missed a successful SMTP response. Be optimistic that the message is
-        // delivered also.
+
+        // It sometimes happens that a slow server (usually a classical email server)
+        // receives a message via SMTP,
+        // but then the connection to the server dies before it sends the OK response.
+        // In order to handle this case, we delete the SMTP send jobs if we receive our own message via IMAP.
+        //
+        // Now, messages with long recipient lists are split into multiple SMTP jobs.
+        // In this case, we only want to delete the SMTP job that was sent to self
+        // because this is the only chunk we can be sure was sent out.
         let self_addr = context.get_primary_self_addr().await?;
         context
             .sql