WHY DID SERENA WILLIAMS DO IT?

Because she has a really bad temper (natal Mars square natal Uranus). Serena wouldn't want you to know this, but she is an angry chick. That's because Libra people always want people to like them. It's very important that they appear to be charming. But you don't want to piss her off! Seriously, it's not just size that counts. She can flatten you with her words!

You won't find many people with a better chart than hers. So what's the problem? Could it be another person with a natal Sun/Jupiter conjunction (the world is their play pen) who takes the good life for granted?

This won't be the time that Serena learns that lesson, because it is unlikely with her good aspects she will be reprimanded.

Her progressed Moon is in nitpicking Virgo, final degrees, so it will be moving to likable Libra. This should be the last we hear from her -- for now.