diff --git a/bayes_opt/util.py b/bayes_opt/util.py
index 099715ef..a936221d 100644
--- a/bayes_opt/util.py
+++ b/bayes_opt/util.py
@@ -83,6 +83,8 @@ def __init__(self, kind, kappa, xi, kappa_decay=1, kappa_decay_delay=0):
         self._kappa_decay_delay = kappa_decay_delay
 
         self.xi = xi
+        
+        self._iters_counter = 0
 
         if kind not in ['ucb', 'ei', 'poi']:
             err = "The utility function " \