Eg.  I bake things that require you start baking at one temp (eg Bake for 10 mins at 450) then drop the temp to a lower temp and continue baking for 25 mins at 400.  Because this oven shuts off when the timer runs out, I can not use the timer when baking. Also if you are cooking something and it is not fully cooked, you have to turn the oven on again to continue cooking!!!