[smudgie]

I think it is the same reason as to why the odds have Brian Dowling as favourite to win. Popularity. (or lack of it)
I know both Makosi and Nadia are entertaining, but when it comes down to the vote, they are least liked out of who is up for eviction. It does not seem fair, especially when you have the quiet bores sailing under the radar, but it has always been this way.
The same reason Nikki will have a hard job to win, her tantrums and face pulling may be entertaining, but at the same time it is very irritating, therefore she will be voted out.