Cheap skates are bad enough. Cheap brake pads made of hard plastic instead of a grippy material are downright dangerous!
I recently used a pair of skates I would never buy for myself nor recommend to a student. This was one of those no-name brands sold at under $50 and constructed of the cheapest materials. Even without knowing the price range, I could tell they were cheap because they had very thin padding around the ankles and bendy plastic buckles. Cheap components like these usually result in a painful or poor fit, or buckle breakdowns that can't be repaired. Fortunately, poor quality of that type is easy to see, and informed buyers know to avoid it.
Unused, the brake looked pretty normal, color and shape-wise. It was only when I tried braking at the bottom of a hill that I discovered how slippery it was. This brake pad was totally unlike the grippy material on the Rollerblade, Salomon and K2 skates I've owned. It was almost as if it had been molded from the same plastic used for the buckles! My photos show what it looked like after 15 minutes of repeated braking, maybe 20 stops.
What did it feel like? It was more unstable and ineffective than any other standard heel brake I've ever used. At the moment of highest friction, the braking skate would suddenly squirt off to one side. It took concentration and muscle to keep it centered in front of my body where the friction gained from good leverage contributes to a full stop. As far as I'm concerned, this unpredictable behavior is a safety hazard for any skater at any level.
This is a perfect example of "you get what you pay for." I'd almost be willing to bet the manufacturer doesn't even sell replacement brake pads. At this price range, the skates themselves are designed to be disposable!
Friends don't let friends buy cheap skates!
See my purchasing advice in How to Shop for Your First Pair of Inline Skates. Thus ends my public service message.