That awkward thing you have to do to get the blanket in the right way.
During my childhood, I fondly remember, I found it strange that there was a shoe specifically designed for each foot. Why couldn't the left shoe fit on the right foot? Gradually, I started thinking about other things too. And realised that many things don't make sense.
For one, beds are usually shaped like rectangles. Why must sheets and blankets be shaped this way too? Maybe it looks better? But I guess blanket designers need to keep in mind he benefit of the person, not the bed.
Suppose it's a cold night and wake up feeling cold in your legs. You try to cover the whole body by adjusting the blanket over your legs. Now you do a kick-thing to get it the correct way. So why can't have be square-shaped or even circular blankets? It would be worth it.