The more specific you define a goal, the more specific the failure becomes. The more your goal has measurable criteria, the more likely you are to achieve it and the more accurate the conditions are when you did not achieve it.
It is easier to have no goals and therefore never really fail. But in the long run you fail over and over again. The price of not setting goals is a life in which you have never achieved anything. The ultimate failure.
If you already know that you cannot achieve 90% of your goals, set yourself unattainable goals. If you know that you will probably miss, at least aim at the moon and be happy if you catch a few stars. It’s better to have unattainable goals and succeed in failing halfway.