The combination of "work" and "out" to form our common term "workout" is no accident.
What are you trying to work out when you exercise? What are you solving for? What problems are you addressing?
"Just doing it" is bogus both as an approach to the physics of exercise and as a reason for your exercise effort.
Occasionally reminding yourself about your "why" for exercise is a useful exercise in itself.
Not having something to work out in your workouts - something real and visceral and meaningful to you - might make your exercise more of a fleeting pastime than a core habit.