Errrmm... Saying that there are always signs (and there really are! ) is not to any extent victim-blamey!
My dear grandad organised private lessons in a creative discipline for me when I was 9 - 10 years of age. The lessons were with his very close life-long friend and neighbour - an elderly man in a wheelchair. That man abused me.
Did my grandad know, did he see any signs? Of course not!! He'd probably kill the man had he any inkling. I don't blame my grandparents at all there - they were not his target after all. They wouldn't have known. The signs were reserved for me.
I do sometimes wonder if now, with an adult capability of understanding interactions and conversations would I be able to foresee this danger?
In hindsight - would my Grandad realise that there were signs all along with this man? Some unusual interest in being around children... Something. Would my grandad even wish to contemplate the signs? The reality of finding some would be too hard to bear via unfounded guilt! But I bet, I bet my top dollar that there were signs.
One can eat a pack of chocolate buttons and get away with no signs (quite some effort still 😁)
It's impossible however to have a whole another disgusting, evil, manipulative personality without it showing somewhere. It always wants to show because it's thoroughly enjoyed.
All those docu-series like "Who did I marry?," Evil lives here"... always signs. Even though families still claim there were literally none. There was a whole library of signs, you just didn't have the dictionary. Or context, or hindsight (always helpful 😐)
Maybe I'm just a cynical old biatch and read into everything and explore all the negatives and then ride the wave of the confirmation bias (even a broken clock is correct twice a day). Maybe that.