Earlier quoted context omitted.
Most sports have a habituation threshold you need to overcome so it becomes an enjoyable habit. Running is probably one the steepest imho.
Gym is the steepest. Three years in and I still hate it.
You move weight around, later you move the same around a bit more (yay!), or move a heavier weigh around (yay!).
You get to really know what your body is capable of.