system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why does semen change from a gel state to a more liquid state some minutes after ejaculation?
gpt
ELI15 version:    
it coagulates first, so it gets harder (and not drip *out*; if you know what i mean)   
After 15-30 minutes "some stuff" that are in there, start to work and de-coagulate the semen.   
so the sperms can go *where they should* and make a baby.    

ELIPhD version:     
After ejaculation, the latter part of the ejaculated semen coagulates immediately,forming globules, while the earlier part of the ejaculate typically does not. After a period typically ranging from 15 – 30 minutes, prostate-specific antigen present in the semen causes the decoagulation of the seminal coagulum. It is postulated that the initial clotting helps keep the semen in the vagina, while liquefaction frees the sperm to make their journey to the ova.