diff --git a/Runtime/Core/Animation/UISizeDelta.cs b/Runtime/Core/Animation/UISizeDelta.cs
index 94d09d8..c4eaf80 100644
--- a/Runtime/Core/Animation/UISizeDelta.cs
+++ b/Runtime/Core/Animation/UISizeDelta.cs
@@ -41,7 +41,7 @@ namespace AlicizaX.AnimationFlow.Runtime
 
         public override bool Valid()
         {
-            return target != null && duration > 0;
+            return target != null;
         }
 
         public override float Duration()