That made me wonder for the first time what goals one might have (beyond learning and having fun) for painting outdoors. (Of course, your first goal, before you even head out, is to banish the inner critic...you can just say, "Bye for now!")
On one end of the continuum, there would be air castles like "Have a significant impact the art world, paint what has never been painted before, make people see things in a new way, make a living as a painter, be a famous teacher..." For most of us, not likely to happen in this lifetime.
Then, closer to the center would be goals like "Create expressive mementos of people, places and pets; practice observing nature and creating compelling compositions; communicate a mood or perspective..." Attainable, perhaps.
At the other end would be goals that one can never fail to achieve: "Practice perspective and proportion, explore the effect of certain colors on each other and on the viewer, experiment with mixing colors, try out different kinds of brush-strokes, discover your strengths, enjoy the interplay of paint, brush, surface and vision, pay attention..." And in the process, create something absolutely unique...something else that you can never fail to do.
Of course, you might want to ask yourself, who is setting these goals, really? The real you, or the anxious ego? The marketplace, the instructor, the cohort, the client? Just being aware of all the potential static in the atmosphere can help us tune in to a clear signal.