diff --git a/linear_programming/simplex.py b/linear_programming/simplex.py
index a8affe1b72d2..835b42d4ce5e 100644
--- a/linear_programming/simplex.py
+++ b/linear_programming/simplex.py
@@ -302,7 +302,11 @@ def run_simplex(self) -> dict[Any, Any]:
                 self.tableau = self.change_stage()
             else:
                 self.tableau = self.pivot(row_idx, col_idx)
-        return {}
+        message = (
+            f"Simplex did not converge within {Tableau.maxiter} iterations. "
+            "The problem may be cycling or unbounded."
+        )
+        raise ValueError(message)
 
     def interpret_tableau(self) -> dict[str, float]:
         """Given the final tableau, add the corresponding values of the basic