Moved in with partner last year, and we don't argue about the toilet seat (it's always down) we argue about flushing the damn thing.
I believe the toilet should be flushed every time, regardless of whether it's a 1 or 2. Partner thinks it should only be flushed when it's a 2. He pees and leaves the loo unflushed and I can't stand it!
The other day he had a bath and left the loo Unflushed. The loo is next to the bath, and I was disgusted - how can he have a nice clean bath next to an unflushed toilet??
He says it's a waste of water but I don't care, I want good hygiene.