diff --git a/paynt/synthesizer/synthesizer_ar.py b/paynt/synthesizer/synthesizer_ar.py
index 1af7788c..b69d381b 100644
--- a/paynt/synthesizer/synthesizer_ar.py
+++ b/paynt/synthesizer/synthesizer_ar.py
@@ -113,6 +113,8 @@ def synthesize_one(self, family):
             family = families.pop(-1)
             self.verify_family(family)
             self.update_optimum(family)
+            if not self.quotient.specification.has_optimality and self.best_assignment is not None:
+                break
             # break
             if family.analysis_result.can_improve is False:
                 self.explore(family)