If it was wet & you didn't "milk" the pods they might have rotted. If they were late blooming they wouldn't have ripened enough. If you used insecticide when the plants were in bloom you might have done in the bugs that would have pollinated the blooms. If the bees weren't there when the plants were in bloom, you need to flit about w/ paintbrush in hand like I do & pretend you're the bees! :)