You know "stability"? As in "core stability", "spinal stability", "shoulder stability", etc? Yes, stability is important, but sometimes we treat stability as though it means we should hold parts of our body rigid and never let them move.
But the technical definition of stability is how well a system can return to an orientation after a perturbation - or in other words, how much *control over movement* there is.
We have stability in our body when we're able to control the ranges of motion that our joints have. That way our body can *move* (not hold rigid all the time), but if there's an element of control there, then there is stability.
Sometimes people are told by doctors, physical therapists, or other health care practitioners that they have "instability" or are "unstable" and therefore shouldn't practice yoga. But if a yoga teacher makes stability a priority (the accurate definition of stability, that is - not the inaccurate one that tends to lead to rigidity and movement avoidance!), then that teacher's yoga class could be a great place for that person!
If you don't have yoga teachers who focus on stability in your area, consider trying out my online class library, which features classes from myself and other special guest teachers who all make stability a priority in our yoga teaching. Your body might liiiike!