diff --git a/scss/_functions.scss b/scss/_functions.scss
index 77b8c8f104..d2cc91d57a 100644
--- a/scss/_functions.scss
+++ b/scss/_functions.scss
@@ -21,12 +21,12 @@
 }
 
 // Starts at zero
-// Another grid mixin that ensures the min-width of the lowest breakpoint starts at 0.
-@mixin _assert-starts-at-zero($map) {
+// Used to ensure the min-width of the lowest breakpoint starts at 0.
+@mixin _assert-starts-at-zero($map, $map-name: "$grid-breakpoints") {
   $values: map-values($map);
   $first-value: nth($values, 1);
   @if $first-value != 0 {
-    @warn "First breakpoint in `$grid-breakpoints` must start at 0, but starts at #{$first-value}.";
+    @warn "First breakpoint in #{$map-name} must start at 0, but starts at #{$first-value}.";
   }
 }
 
diff --git a/scss/_variables.scss b/scss/_variables.scss
index bbd92a91aa..74b8617af7 100644
--- a/scss/_variables.scss
+++ b/scss/_variables.scss
@@ -196,7 +196,7 @@ $grid-breakpoints: (
 ) !default;
 
 @include _assert-ascending($grid-breakpoints, "$grid-breakpoints");
-@include _assert-starts-at-zero($grid-breakpoints);
+@include _assert-starts-at-zero($grid-breakpoints, "$grid-breakpoints");
 
 
 // Grid containers