If it uses alkalines it has to. Alkalines only provide 1.5V when they're
brand new. They quickly degrade to around 1.2V for most of their
lifetime and then drop off rapidly to nothing when they're dead.

Actually, alkalines steadily decline from 1.5V to around 0.8 when dead. They
don't particularly hang about any particular voltage figure, although the
chart is not entirely linear, so the drop is slowest around the 1.2V mark.

Christian.