I can only speak from my personal experience.
My first attempt was impulsive, I was half thinking it might be okay if this was the end right now, half thinking I wanted to be rescued. I downed prazepam pills and a couple sips of rum. Someone called the emergency for me cause I did that while walking along the Quais de Paris, and in the moment I felt glad there were so many souls dedicated to saving me and taking care of my wellbeing.
The second attempt had more thoughts and reflection put into it, but I ended up having a psychosis episode in the middle of it which landed me to a 72h jail hold right away, followed by court ordered 3 weeks in a psych ward. I felt confused, angry, disgusted by myself, dirty, frustrated that it didn't work but still felt the need to be comforted by my close family and friends even though I basically would have abandonned them all should my attempt have worked, so I felt really horrible. I'm still feeling the aftermath of that one, and I wish with all my being that I would have succeeded. Which is why I'm hanging around this forum.
3rd time's the charm, yeah?