diff --git a/platform/features/plot-reborn/src/directives/MCTPlot.js b/platform/features/plot-reborn/src/directives/MCTPlot.js
index 2b493f71ae..763993f24d 100644
--- a/platform/features/plot-reborn/src/directives/MCTPlot.js
+++ b/platform/features/plot-reborn/src/directives/MCTPlot.js
@@ -370,6 +370,8 @@ define(
                 }
 
                 // Updates the viewport based on the amount of zooming (pinching) user is doing
+                // Pinch inwards (zoom out): distanceRatio > 1
+                // Pinch outwards (zoom in): distanceRatio < 1
                 function updateZoom(midpoint, bounds, distance) {
 
                     // Gets the current midpoint and distance ratio to be used to