I was having a think about why it falls away for me. I think for the first series, the action was the interest with small snippets into the character building. I was looking forward to getting to know the protagonists.
In series two, nothing has changed. In fact, I feel like the character building has took a back seat to the potential 'shock and awe' of the eps (mind you, I have a citizen I work with that has one of the bodily issues shown in the show and the design for the injury was 80% accurate).
For me, that's where 'ER' nips ahead of it as an overall show. I don't know any of the true motions for anyone in 'The Pitt'.
So, now, I'm only invested as I've put in the time as, to me, the show lacks balance.