diff --git a/openhtf/core/phase_executor.py b/openhtf/core/phase_executor.py
index f578fda9..d0eca616 100644
--- a/openhtf/core/phase_executor.py
+++ b/openhtf/core/phase_executor.py
@@ -346,7 +346,7 @@ def _execute_phase_once(
     # Refresh the result in case a validation for a partially set measurement
     # or phase diagnoser raised an exception.
     result = override_result or phase_state.result
-    self.logger.debug('Phase %s finished with result %s', phase_desc.name,
+    self.logger.debug('Phase %s finished with result %r', phase_desc.name,
                       result.phase_result)
     return (result,
             phase_thread.get_profile_stats() if run_with_profiling else None)