Why are cluster munitions so notorious for leaving unexploded bomblets around?

Question

Is it poor build quality or are they not designed to explode on impact?

In: 1717

Answer 1

https://en.wikipedia.org/wiki/Ottawa_Treaty

All US landmines now self-destruct in two days or less, in most cases four hours. While the self-destruct mechanism has never failed in more than 65,000 random tests, if self-destruct were to fail the mine will self-deactivate because its battery will run down in two weeks or less. That compares with persistent anti-vehicle mines which remain lethal for about 30 years and are legal under the Ottawa Convention.[107][108]”