I purchased a set of 12 of these clear plastic hooks for use in my daughters rented flat.
I followed the instructions to the letter and left the adhesive to set overnight before using.
Within about a minute of hanging a childs coat the hook failed. I had similar results with the other hooks.
Interestingly the tab was still firmly attached to the wall, it was the attachment to the plastic hook that had failed.
Seems to me to be a useless product that is not fit for purpose