diff --git a/lib/gears/object.lua.in b/lib/gears/object.lua.in
index 4782314c8..2a3e5ef20 100644
--- a/lib/gears/object.lua.in
+++ b/lib/gears/object.lua.in
@@ -27,7 +27,7 @@ end
 local function find_signal(obj, name, error_msg)
     check(obj)
     if not obj._signals[name] then
-        error("Trying to " .. error_msg .. " non-existent signal")
+        error("Trying to " .. error_msg .. " non-existent signal '" .. name .. "'")
     end
     return obj._signals[name]
 end