system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why do bees die when they lose their stinger?
gpt
The stinger of the most common bee species has a barb in the end, and the connection to the abdomen of the bee is physically weak enough that the bee is able to tear its exoskeleton/skin by crawling/pulling away.  The resulting wound damages the bee's internal organs and allows loss of vital fluids.

The advantage to this is two fold - the stinger retains enough body organs to continue injecting poison into the stung thing (thus teaching the lesson "mess with bee hives and you will regret it!") and the bee is (briefly) able to fly away, thus spreading the pheromones associated with dying through the local area.  This scent brings more angry bees (and more lessons) to the immediate area.

Wasps have a barbless stinger, as do queen bees, reflecting their relative worth to their groups.  (The queen is the mother of all bees in the hive, and wasps do not have a non-fertile gender as do bees, so the loss of a single wasp means the loss of that genetic line.)