diff --git a/dbms/src/TiDB/Schema/SchemaSyncService.cpp b/dbms/src/TiDB/Schema/SchemaSyncService.cpp
index adc1821c00a..419a2f28e4a 100644
--- a/dbms/src/TiDB/Schema/SchemaSyncService.cpp
+++ b/dbms/src/TiDB/Schema/SchemaSyncService.cpp
@@ -307,6 +307,7 @@ bool SchemaSyncService::gcImpl(Timestamp gc_safepoint, KeyspaceID keyspace_id, b
                     storage->getTombstone(),
                     gc_safepoint,
                     canonical_name);
+                succeeded = false; // dropping this table is skipped, do not succee the `last_gc_safepoint`
                 continue;
             }
             else
@@ -346,7 +347,7 @@ bool SchemaSyncService::gcImpl(Timestamp gc_safepoint, KeyspaceID keyspace_id, b
         }
         catch (DB::Exception & e)
         {
-            succeeded = false;
+            succeeded = false; // dropping this table is skipped, do not succee the `last_gc_safepoint`
             String err_msg;
             // Maybe a read lock of a table is held for a long time, just ignore it this round.
             if (e.code() == ErrorCodes::DEADLOCK_AVOIDED)
@@ -400,7 +401,7 @@ bool SchemaSyncService::gcImpl(Timestamp gc_safepoint, KeyspaceID keyspace_id, b
         }
         catch (DB::Exception & e)
         {
-            succeeded = false;
+            succeeded = false; // dropping this database is skipped, do not succee the `last_gc_safepoint`
             String err_msg;
             if (e.code() == ErrorCodes::DEADLOCK_AVOIDED)
                 err_msg = "locking attempt has timed out!"; // ignore verbose stack for this error