It's not for the oven, it's for when they boil in water. A proper bagel is boiled first, then baked. It's also used for transportation and display by threadin

It's not for the oven, it's for when they boil in water. A proper bagel is boiled first, then baked. It's also used for transportation and display by threading a rod or string through the hole, but the main reason is for even boiling. Same as a doughnut (except that is boiled in oil).