diff --git a/frc971/control_loops/drivetrain/splinedrivetrain.cc b/frc971/control_loops/drivetrain/splinedrivetrain.cc
index 1222ae0..c467e1f 100644
--- a/frc971/control_loops/drivetrain/splinedrivetrain.cc
+++ b/frc971/control_loops/drivetrain/splinedrivetrain.cc
@@ -170,6 +170,8 @@
       has_started_execution_ = false;
     }
     mutex_.Unlock();
+  } else {
+    VLOG(1) << "Failed to acquire trajectory lock.";
   }
 }