This makes the poison stronger.
The sting of the bee is serrated and gets stuck in the skin of vertebrates along with the poisonous apparatus torn from the bee’s abdomen. This leads to the death of the insect, but the storage bag connected to the sting continues to contract, squeezing out new doses of poison.
This is how bee colonies of tens of thousands of individuals are protected, where worker bees are not of great value. For a bumblebee or aspen family (where there are no more than a few hundred individuals), the death of each worker is palpable. These insects sting without dying.