HN is basically the most important part of YC -- the branding part.
If it didn't exist, many of the very successful startups it has a stake in likely would not have applied to it.
Now, one of HN's most important functions is to 1) advertise the YC-funder startups, or at least raise their name-recognition, b) advertise YC, advertise the VC's, and c) jobs ads for YC companies.
HN and pg whatever it can to optimize these 3 functions.
What HN is
If it didn't exist, many of the very successful startups it has a stake in likely would not have applied to it.
Now, one of HN's most important functions is to 1) advertise the YC-funder startups, or at least raise their name-recognition, b) advertise YC, advertise the VC's, and c) jobs ads for YC companies.
HN and pg whatever it can to optimize these 3 functions.