The way you see things - your attitude - is the most important factor in your success.
Put all excuses aside and remember this: YOU are capable.
There's no traffic jam on the extra mile.
I wouldn't say 'most' people are prone to negativity. I think it's probably that most people allow negativity to color their thinking, depending on circumstances, but I also believe most people make the necessary efforts to return to positive thinking as quickly as possible.
Don't give up just because of what someone said. Use it as motivation to push harder.
It makes no difference where you go, there you are. And it makes no difference what you have, there’s always more to want. Until you are happy with who you are, you will never be happy because of what you have.