I have to remind myself, every once in a while, that my daily writing goal is not to make another novel happen, but to write 600 words a day.
A novel is a goal and has an end. It has a quality of being good or bad that can be judged. I will spend a lot of time judging its qualities, wondering about its potential worth and the value of my time continuing to work on it. Even on a good day, this can be a hinderance because I will look at my good writing and compare it to my bad writing, and see my written work as being a dis-organized mess that sucks as a gestalt.
But focussing on process? I'm worried about what made it hard or easy to hit my 600 words. What made the process enjoyable? How was it a struggle? Where their parts that were repeatable and what was a fluke? Am I going to hit my goal today, or am I going to blow past it and build up my reserve word count?
The most important part of focussing on process is to monitor whether or not it is sustainable. Does this process give value to my life? Am I deriving a sense of virtue in the process? Does this feel like it's working towards how I perceive myself to be as a person, at the end of my days?
Those constant questions are how I refine the process. Examining my inner state as well as the quantity, and even the quality, of my output gives me the tools to improve. At no point will I ever stop finding something to improve, and with this the process becomes my art.