A Practice!
Because it changes with you
Much of everything is just noise
Every month there is a new exercise, a new posture, a new piece of equipment, a new style, a new way, a better promised future that will fix everything before it and yet the next month it will be "obsolete". Every time this happens a new promise is made, the old one is broken and your trust in the system is eroded. This never ending cycle is needed to keep your attention away from the real underlying problem, that you actually dread doing your workouts. Why would you commit to something that always changes?, and never delivers the promised results.
The joy of missing out
The Practice is a constant in your day, in your schedule, in your life. You go in, pay the price of effort and you get a better, more functional body in exchange. The basics of the body's movement won't change any time soon, therefore neither the basics of your exercises won't. Your shift from fearing of missing out "the latest, best one" to laying a solid foundation that you can build upon, day after day.
Your anatomy didn't change
So why your workouts always change what you should be doing? You could argue that a new muscle has been discovered, and how often does that happen? Up until today, the main movements of the body are based on pushing, pulling and carrying stuff; and they won't change any time soon. Just a few exercises for each movement category will yield the results you need.
But changes are inevitable
Cause by the results of the effort you paid. Good change keeps the few things yielding results introducing variation in the time required, some shorter and some longer; in the effort required, some lighter and some heavier; in the aimed targets, some loose and some focused.