Smart Guides buggy at artboard corners
When resizing snapping shapes or objects, Illustrator smart guides alert user that object is being snapped to corner or intersect, however it isn't actually, and it's not until you zoom right in that you realise it hasn't.
Snap to Pixel is turned off. Smart Guides are turned on.
There is no 'anchor' at that location other than the Artboard Edge.
Here's a video showing another example of this issue, this time in Windows 10