The earths is an ovary (egg), a meteor is a sperm. Many sperms fail, but the meteor that succeeds may create or destroy life. A very simplistic use of words (literally).
Panspermia or not, you still have to explain where the very first life came from. How did it get into the meteorites? ------------------ I am; therefore I think.
I think life, or atleast the ingredients for life, are quite abundant throughout the universe. An organism having the right conditions in order to spawn, or more importantly, thrive, is the key. You can't make Kool-Aid without water and a spoon to stir it. But how many cosmic spoons are in the universe drawer?
I've found that Kool-Aid mixes with water much better if you shake it! No spoon needed here. Please Register or Log in to view the hidden image!