diff --git a/requirements-py3.txt b/requirements-py3.txt
index 1ddc482c1..461d77925 100644
--- a/requirements-py3.txt
+++ b/requirements-py3.txt
@@ -1,3 +1,7 @@
+# The order of packages is significant, because pip processes them in the order
+# of appearance. Changing the order has an impact on the overall integration
+# process, which may cause wedges in the gate later.
+
 oslo.config>=1.2.1
 oslo.utils>=0.2.0
 stevedore>=0.14
diff --git a/requirements.txt b/requirements.txt
index efb513e3f..932b534b9 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -1,3 +1,7 @@
+# The order of packages is significant, because pip processes them in the order
+# of appearance. Changing the order has an impact on the overall integration
+# process, which may cause wedges in the gate later.
+
 oslo.config>=1.4.0.0a3
 oslo.utils>=0.2.0
 stevedore>=0.14
diff --git a/test-requirements-py3.txt b/test-requirements-py3.txt
index 1c922e795..9ed4aca4c 100644
--- a/test-requirements-py3.txt
+++ b/test-requirements-py3.txt
@@ -1,3 +1,7 @@
+# The order of packages is significant, because pip processes them in the order
+# of appearance. Changing the order has an impact on the overall integration
+# process, which may cause wedges in the gate later.
+
 # Hacking already pins down pep8, pyflakes and flake8
 hacking>=0.9.1,<0.10
 
diff --git a/test-requirements.txt b/test-requirements.txt
index 610a05279..78fd3a13e 100644
--- a/test-requirements.txt
+++ b/test-requirements.txt
@@ -1,3 +1,7 @@
+# The order of packages is significant, because pip processes them in the order
+# of appearance. Changing the order has an impact on the overall integration
+# process, which may cause wedges in the gate later.
+
 # Hacking already pins down pep8, pyflakes and flake8
 hacking>=0.9.2,<0.10