diff --git a/server/cluster/cluster.go b/server/cluster/cluster.go
index 3b33c46b09e..b523e99c4a9 100644
--- a/server/cluster/cluster.go
+++ b/server/cluster/cluster.go
@@ -418,8 +418,11 @@ func (c *RaftCluster) checkTSOService() {
 			}
 			c.SetServiceIndependent(constant.TSOServiceName)
 		} else if c.opt.GetMicroServiceConfig().IsTSOFallbackEnabled() {
-			// TSO server is not available, we need to initialize the PD's allocator group and
+			// TSO server is not available.
+			// If TSO fallback is enabled, we need to initialize the PD's allocator group and
 			// let PD provide the timestamp through UnsetServiceIndependent.
+			// Otherwise, we will wait for the TSO service to be available.
+			// In this case, no timestamp will be provided.
 			if !allocator.IsInitialize() {
 				log.Info("initializing the global TSO allocator")
 				if err := allocator.Initialize(0); err != nil {
diff --git a/server/config/config.go b/server/config/config.go
index c8988939d09..c245bfa4567 100644
--- a/server/config/config.go
+++ b/server/config/config.go
@@ -253,7 +253,7 @@ const (
 	maxCheckRegionSplitInterval     = 100 * time.Millisecond
 
 	defaultEnableSchedulingFallback = true
-	defaultEnableTSOFallback        = true
+	defaultEnableTSOFallback        = false
 )
 
 // Special keys for Labels