diff --git a/pkgs/typed-racket-pkgs/typed-racket-lib/typed-racket/optimizer/float-complex.rkt b/pkgs/typed-racket-pkgs/typed-racket-lib/typed-racket/optimizer/float-complex.rkt
index 65211a04..3de0dbf8 100644
--- a/pkgs/typed-racket-pkgs/typed-racket-lib/typed-racket/optimizer/float-complex.rkt
+++ b/pkgs/typed-racket-pkgs/typed-racket-lib/typed-racket/optimizer/float-complex.rkt
@@ -43,10 +43,10 @@
   (log-opt opt-label arity-raising-opt-msg))
 (define-syntax-rule (log-missed-complex-expr)
   (log-missed-optimization
-    "Non complex value in complex arithmetic"
+    "non-complex value in complex arithmetic"
     (string-append
-      "This expression has a non FloatComplex type and thus cannot "
-      "be promoted to unboxed arithmetic.")
+      "This expression has a non-float Complex number type. "
+      "The optimizer could optimize it better if it had type Float-Complex.")
     this-syntax))
 
 ;; If a part is 0.0?
diff --git a/pkgs/typed-racket-pkgs/typed-racket-test/tests/typed-racket/optimizer/tests/complex-exp.rkt b/pkgs/typed-racket-pkgs/typed-racket-test/tests/typed-racket/optimizer/tests/complex-exp.rkt
index 29efe631..9834c8dc 100644
--- a/pkgs/typed-racket-pkgs/typed-racket-test/tests/typed-racket/optimizer/tests/complex-exp.rkt
+++ b/pkgs/typed-racket-pkgs/typed-racket-test/tests/typed-racket/optimizer/tests/complex-exp.rkt
@@ -1,6 +1,6 @@
 #;#;
 #<<END
-TR missed opt: complex-exp.rkt 16:3 (exp 0) -- Non complex value in complex arithmetic
+TR missed opt: complex-exp.rkt 16:3 (exp 0) -- non-complex value in complex arithmetic
 TR opt: complex-exp.rkt 16:0 (- (exp 0) 1.0+2.0i) -- unboxed binary float complex
 TR opt: complex-exp.rkt 16:11 1.0+2.0i -- unboxed literal
 TR opt: complex-exp.rkt 16:3 (exp 0) -- float-arg-expr in complex ops