'Just For You' not updating

[Craigski]

I only noticed the 'Just For You' section under Home recently.  So not sure if it's a new feature?

It's the section under Home that appears to suggest Playlists based on your tastes. 

Which sounds neat, but on mine it has never changed since I first noticed it.  The same 14 playlists are being suggested every day.  Is it supposed to change?  If so, how often?