A fair, shall we say 'inquiry' in any and every case is what that individual's problems actually are.
I'm not going to go over all the issues which might be unsolvable or permanent.
Attitude overall is certainly indicative. Another thing to factor in might be brain chemistry.
It certainly isn't hard to see why someone with terminal conditions (disease, injury, genetically inherited disorders, etc.) would start disliking life after so long.
Part of it, I think, is how the long road is forgone in an age of instant gratifications. We (the common people) don't learn to root ourselves in reality, so consequently we drift and dream on a perch until we get knocked off and have to live in a rut. It repeats itself over and over. When you have a solid foundation then it's harder to 'knock you down' so to speak. I'm a realist. It's okay to both dream and see difficulty, but just keep it all in perspective.
Point being is perception and attitude plays a bigger role in suicide prevention than one might think.
On the other hand...I can't say anything to those who see no logical reason to keep going if their situation isn't going to get any better (a.k.a. hopeless without drama and hyperbole).
Maybe something to consider is what makes life worth living in the first place despite complication and difficulty.