It's just hard to get particularly invested in this season. The casting was decent, but a lot of the houseguests are just very blah, and don't seem to be particularly emotionally involved. There are no bloodthirsty rivalries forming, and drama has been at a total minimum apart from a few early headbutts.
The actual content of the evictions so far hasn't been that bad. We've already had a neck-and-neck eviction race, a major backdooring and we should have had a classic blindside in Frank. I think it's just everything in between that makes this series a bit of a hard watch. There doesn't seem to be a whole lot of game being played, and nobody really seems to be stirring the pot after noms are finalised.