Often I think like you, but it is wrong I guess. I wonder if you are thinking of a particular person or have a picture in mind when you think about "people that are cut out for life". I wonder because I do not think such a thing exists. Tell me if I am wrong, but when I read your post the idea of "fate" or "destiny" come to my mind. I do not know what you think, but to me "fate" does not exist. I think there is no place where your fate of not being cut out for life is written. Although I have to admit that some of us has been given some particular characteristics through genetics, early experiences, etc that make living harder, to me the worst part is our common heritage, I mean, the shortfalls that all human beings share. The good news is that our brain has some plasticity, and we can change our thoughts and behaviors. Perhaps there are some people that could not improve their lives even with a lot of effort but I do not think this is your case or mine.