Nobody likes spending 30 minutes untangling a 50m extension cord.
Trouble is, usually we use them incorrectly!
It turns out you have to read the fine print: You can only use the full capacity of the reel if you fully unwind the rolly cord.
If you don’t fully unwind the cord, the power rating of the reel drops by a factor of 3, which means the current you can draw drops by a factor of 3, which means you’re likely to destroy the poor thing!
Rolly cords have (usually) thermal circuit breakers, but those breakers are a) cheap, and b) designed to trip at the max current for the reel when the cord is fully unwound.
Technically, this is “overheat protection”, but in my experience it doesn’t work well at all when the cord is still on the reel – even with premium brand reels. The breaker will quickly fail, and you’ll be left with a useless cord reel.
When the cord is still mostly wound on the reel and you pull even slightly too much juice, the whole thing heats up and will then fail shortly – possibly in a spectacular, fiery fashion if you’re unlucky.
So be nice to your rolly cords, and always unroll them fully whenever you use them!
Carry on, then!