Question…
What are the 100 million or so other sperm doing as a man impregnates a women .??..or the same question can be put , applying to any male of any species , although the number of sperms differ .

Only one makes it …..the rest must take rebirth

There is a chemical signal sent to attract specific sperm .
See.

Follicular fluid from one female was better at attracting sperm from one male, while follicular fluid from another female was better at attracting sperm from a different male,” said Professor Fitzpatrick.

“This shows that interactions between human eggs and sperm depend on the specific identity of the women and men involved.”

“
The idea that eggs are choosing sperm is really novel in human fertility
Professor Daniel Brison