Few players attain the attitude and mindset that is detailed here. Most don't even know that it exists. Yet it is experienced by many players and is most often discovered by accident rather than by intention.The development (or growth) of your game is not simply a matter of improving skills and gaining experience. There is also a necessary mental expansion that occurs which improves your appreciation and enjoyment of the game. This is what makes playing pool worthwhile throughout a lifetime.
The process is an uneven pathway. What was important a year ago is not so today. Even your favorite game will change over time. It might start out as 8 Ball, move to 9 Ball, transition to straight pool, and then explore the possibilities of 1 Pocket. You may even enjoy multiple player games such as Golf for a decade or two. Snooker and 3-cushion Billiards can have a fascinating attraction.
Regardless of these transitory fads, each of these offers up the "thrill of victory" and the "agony of defeat". What does happen over the years is a gradual realization that the importance of the game does not revolve around the winning (however enjoyable) and losing (however painful).
Eventually, your purpose and satisfaction is not going to come from the winning of games, but from moving closer and closer to perfect control. There are many examples of how this can be achieved. In straight pool, one level will be when you can play through two racks of pool. Then it will be when you achieve your first century (100 balls). In other pool games, you can set up various goals. As you achieve them, you set higher goals.
It can be transitory, such as a perfect shot with the cue ball stopping on the intended square inch of the table. Or it could be successfully running the rack. The satisfaction of either achievement can justify an entire evening at the pool hall.
Once this mindset is adopted, in many ways the game becomes more complex. You have to consider dozens, even hundreds of things when selecting a shot. You include in your evaluation the various pathways of different cue ball spins applied with different speeds. Winning becomes a mere chalk mark. Much more important will be how close you got to perfection.