diff --git a/slides/containers/Copy_On_Write.md b/slides/containers/Copy_On_Write.md
index aedb8da0..ae8ce692 100644
--- a/slides/containers/Copy_On_Write.md
+++ b/slides/containers/Copy_On_Write.md
@@ -327,9 +327,7 @@ class: extra-details
 
 ## Which one is the best?
 
-- Eventually, overlay2 should be the best option.
-
-- It is available on all modern systems.
+- In modern (2015+) systems, overlay2 should be the best option.
 
 - Its memory usage is better than Device Mapper, BTRFS, or ZFS.