The magnet wasn't strong enough to hold the weight of ...
351353
The magnet wasn't strong enough to hold the weight of one of the "gems". Even if you try to put the gem on the line by hand it won't hold. Then the handle broke with normal use after 2 minutes of being out of the package.
1128790
The adhesive holding it to the magnet gave out once, it fell, and a small piece chipped off. Glue does not seem to hold great promise in repairing it and I think the magnet would be better mounted inside a small pocket of fabric rather than glue.

Aside from that, the space is adequate for the folders and papers I intended to store in it, but try to find something a little better built or at least something a little more robust.
4447471
Magnet was not strong enough to hold LG G6 phone with Spigen rugged case in place when used in Jeep Wrangler.  Just slid off.  It might have worked if I removed the case, but for me that wasn't an option to have to to do each time I wanted to use this.
4146842
Used for a removable sign on a car. Lost both sides in a couple of weeks. Magnet is pretty weak
4080972
The screwpop was too long or the magnet wasn't strong enough to be useful. My keys aren't very heavy and the magnet falls right down.
1847825
I ended up attaching strip magnets to these with double side tape, the original adhesive will not hold the weight.
2898320
The magnets are weak.  The shape/size is appropriate for my needs, however, I would not purchase again unless the product came with stronger magnets.
1226073
I ended up using the stickers that came with this because the magnets aren't strong enough to hold it.
3375504
magnetic is not strong enough, big enough but don't think it will hold more than 5/6 dry erase marker, it felt.
1032638
Magnet not that strong. After putting my cards on the left side the phone could hardly close. Plus with the weak magnet I was afraid it may open and lose my cards.
2122069
Poor strength in the magnets causes these jaws to be less than functional at times
1620316
Magnets are not strong enough.  I wanted to use them to put holiday photo cards from friends on the refrigerator; it requires at least two of these to hold up one card...
3682140
Band was coming loose and I lost my watch.  Pretty upset  Magnet wasn't strong enough.
878070
The tiny screws it comes with to hold the larger piece to the ground strip out if your door is solid/heavy.  Also, the magnet is extremely weak - the slightest wind blows the door off the magnet.
394727
This magnet is not strong enough to hold my phone. It also has a rotating socket so that you can position your phone however you like, unfortunately it is completely floppy. It does not hold the position of your choice, it flops about with gravity.

Update: The seller contacted me after reading my review and offered to replace the mount with one that had a stronger magnet. Which worked out pretty well. It's the same style and does indeed have a stronger magnet. i have to say at this point it is worth the money, and nice to know the seller provides great customer service.
4624500
Product works well as a thermal switch, however the magnet is not strong enough to support its own weight on the tin that lines the cavity under my fireplace.  I am going to try some hi-temp silicone to get it to stick in place.
4796789
The magnet on this product is not as good as I was hoping and therefore I wasn't completely satisfied with this product.