Complex systems operate under conditions far from equilibrium. There has to be a constant flow of energy to maintain the organisation of the system and to ensure its survival.
If resources were limitless, i.e., if growth could take place unrestricted, no meaningful structure would evolve. Boundaries, limits and constraints are preconditions for structure.
The theory of self-organised criticality tells us the following. A self-organising system will try to balance itself and a critical point between rigid order and chaos.
The classic definition of stability states that in a stable system small causes produce small effects.
The classical definition of instability, at least as used by Poincaré, is probabilistic. Unstable events are defined as events that have no observable cause.
The system of language transcends the choices of any individual user, and therefore has stability.
In the last analysis, the two facts are interdependent: the sign is exposed to alteration because it perpetuates itself.
When dealing with complex phenomena, no single method will yield the whole truth.