Do low expectation produce low results?

So I am blaming my lack of posting over the last week an a half on the discussion we had in class about being set up to fail. Ever since that conversation I have not been knitting more than once or twice a week and I have not posted anything. I think I unconsciously decided if I am supposed to fail I might as well go ahead and stop. Obviously flawed logic but surprisingly effective in making me stop. This brings me back to the idea of pressure and expectations. I am not sure what I think about the idea that all stress or pressure is negative. Sometimes I need pressure and expectations or else I accomplish nothing. But too much pressure is definitely not a a good thing. The past two days I have enjoyed waking up in the morning and knitting a little. My scarf is coming along and is about two feet long, maybe a little less. I wonder if setting goals is a bad thing? Or maybe it is just that setting goals is fine as long as you are ok with not achieving your goal but getting closer to it. I have often gone the other direction and resist setting any goals because I do not like it when I do not achieve my goal. I like to just try and see what happens without setting specific goals. But then do I accomplish less because I am not "aiming high". I don't know. I guess the real question is what does success look like to me versus what others think success looks like. Am I ok with personal success rather than what is judged to be success by others.