Why does a single orchid capsule produce so many seeds?

Orchid capsules produce a vast number of seeds primarily because of the low probability that any individual seed will land in a location suitable for germination and growth.1

Unlike many other flowering plants, orchid seeds lack endosperm, the nutrient-rich tissue that typically nourishes a developing embryo. Because these seeds are extremely small, light, and dustlike, they are designed for wind dispersal over long distances. However, because they lack their own food reserves, they must rely on a symbiotic relationship with a specific mycorrhiza fungus to provide the necessary nutrients for germination and early development. The production of a massive quantity of seeds increases the statistical likelihood that at least a few will successfully encounter the required fungal partner in a favorable environment.21