Update describe.py

fix-60550

Author: Abhibhav2003

pandas/core/methods/describe.py

@@ -354,9 +354,8 @@ def _refine_percentiles(
     # get them all to be in [0, 1]
     validate_percentile(percentiles)
 
-    # median should always be included
-    if 0.5 not in percentiles:
-        percentiles.append(0.5)
+    if percentiles == []:
+        percentiles.append(0.5)  # By default if percentiles is empty then append 50th percentile.
 
     percentiles = np.asarray(percentiles)