It's always the same with reality shows, which is why I like them. There is a balance to be struck between not being annoying, which often means staying under the radar, and contributing enough to be deemed valuable, which can put you in the spotlight. The personalities of the voters is important too. Extraverts are maybe more likely to prefer people who contribute and are 'good value', whereas introverts might appreciate those who are quieter and give them some space, so a good player will weigh that up, and sometimes have to factor in the viewing public if they have a vote. The reasons for voting someone out are often given as 'I didn't feel we connected', so it's important for the contestants to get on good terms with all the others without being too annoying, and whilst keeping an eye on what is likely to be featured in an edit.
People often seem to see reality TV as 'mindless' (usually those who proudly boast they've never watched it ), but there is a lot more going on than they seem to realise.