Sounds like you need a new toaster! If you're one of those people that like their bread lightly dried with a hint of gold round the edges, suggest you use an ordinary grill and watch carefully.
Some people keep their bread in the fridge or freezer - it needs to warm up before it can toast, so it needs to cook longer, hence the higher setting, but if you don't need it don't use it. This setting is also good where the bread's thicker or if you're toasting crumpets or muffins.
There will always be at least one person in the world who threatens to sue because their toast isn't brown enough, hence the cremation setting, but for the rest of us it's just one of life's little mysteries. Like the eternal question of why you always get left with a few odd socks after doing the washing, even if only matched pairs went in.