Honeybees die after stinging because they leave some of their digestive
tract along with the stinger.

A bee sting may be painful, but that's nothing compared to the fate of the
honeybee once it has lodged its stinger in a victim's skin. Luckily for
both victim and attacker, honeybees usually only sting humans when they are
roughly handled or they feel their hive is threatened. But when they do
sting, it's fatal for them. Honeybees die after stinging because they are
unable to easily remove their stingers from those they attack.