Sperm shortage

https://www.independent.co.uk/news/science/britain-is-facing-a-major-sperm-shortage-9569949.html

A lot of sperm in storage is unsuitable for implanation.

A lot of what remains is the private property of the men who deposited it, or their heirs.

This is how we can have enormous quantities of sperm in storage and still have a sperm shortage.