Most reels you come across for sale these days have a block of text telling you to unwind fully before use.
It's getting people to read it thats the problem. Same as those people who go to a hardware shop, (in fact any shop that sells them, including supermarkets), and just pick one up without checking the rating. Woman next to my daughter used a reel on her tumble-dryer and asked my daughter if I would have a look at it, ("because it was getting quite hot even though she had unwound it"). I asked my daughter to read out what it said on the socket face of the reel. She said, "15 metres Unwind fully before use." I asked if there was a 10A or 13A anywhere on it and she replied, "Yes, it says 10A."
So I told her, it needs one with 13A on it and it should only be as long as the distance between the dryer and the socket and preferably no more than 2 metres. Also recommended she try to find one that has 2.5mm written on it as opposed to 1.5mm