On the product page of BALL-LOCKING QUARTER TURNS and BALL-LOCKING PUSH-PUSH
it is shown that there is a limited guaranteed clamping force of 30N which is 3kg or 50 N which is 5Kg,  this is done by the balls that push against the side of the receptacle.

The product is made so that that the fastener makes sure that both panels are fully connected to each other, and will not wabble.

This is accomplished, by installing the receptacle 0.5mm flush under the surface.

So it comes back to a correct installation.

Check the video showing the fastener in free air: the video shows that you have a slight tolerance between receptacle and stud.
This tolerance is done away when you install the receptacle 0.5mm deeper.
Check this video here: https://youtu.be/BWlmZGGgk-c