Why soil changes?
Is replacing the potting soil really necessary as long as the roots don't need to be trimmed or anything like that?
You can supplement food via chemicals or mixing compost into the top layer so why do you need to change the potting soil for this reason?
Also, I'm pretty sure soil compacts in nature, and no one changes the soil for their plants growing in the ground so why does it need to be done for container plants?
And if soil in containers gets unbelievably compact, versus the ground, why do you need to change it if you use un-compactable soil in the first place? Like when you mix in un-degradable materials.