diff --git a/OpenRA.Game/Translation.cs b/OpenRA.Game/Translation.cs
index 39d51f3244..135fb81562 100644
--- a/OpenRA.Game/Translation.cs
+++ b/OpenRA.Game/Translation.cs
@@ -88,8 +88,8 @@ namespace OpenRA
 
 		public bool TryGetString(string key, out string value, IDictionary<string, object> arguments = null)
 		{
-			if (string.IsNullOrEmpty(key))
-				throw new ArgumentException("A translation key must not be null or empty.", nameof(key));
+			if (key == null)
+				throw new ArgumentNullException(nameof(key));
 
 			try
 			{
diff --git a/mods/common/scripts/utils.lua b/mods/common/scripts/utils.lua
index a7970cedd4..e474aa1254 100644
--- a/mods/common/scripts/utils.lua
+++ b/mods/common/scripts/utils.lua
@@ -38,10 +38,7 @@ end
 ---@param description string key of the translation string
 ---@return number id used to query for the objective later
 AddPrimaryObjective = function(player, description)
-	local translation = description
-	if translation ~= "" then
-		translation = UserInterface.Translate(description)
-	end
+	local translation = UserInterface.Translate(description)
 
 	Media.DisplayMessageToPlayer(player, translation, UserInterface.Translate("new-primary-objective"))
 	return player.AddObjective(translation, UserInterface.Translate("primary"), true)
@@ -52,10 +49,7 @@ end
 ---@param description string key of the translation string
 ---@return number id used to query for the objective later
 AddSecondaryObjective = function(player, description)
-	local translation = description
-	if translation ~= "" then
-		translation = UserInterface.Translate(description)
-	end
+	local translation = UserInterface.Translate(description)
 
 	Media.DisplayMessageToPlayer(player, translation, UserInterface.Translate("new-secondary-objective"))
 	return player.AddObjective(translation, UserInterface.Translate("secondary"), false)