The universe is in constant change: atoms constantly change, things are microscopically moving all the time, you are evolving, the river is never the same, etc. The second time you see a thing like a chair, or even yourself in the mirror, you are not anymore seeing the same thing or person you've seen in the first place. The thing has changed. You are not anymore the same person.
So, strictly, there are no static things, everything is permanent change.
But when you see a rock in the ground (or a person in some situation), it seems completely static. And, following your question, you can describe it, because it doesn't apparently change.
The epistemological issue here is that knowledge is a model of the world, like a map is a model of the terrain.
But the map is not the terrain. In this case, what changes is the terrain, not the map, like a river changes continuously into the terrain, but it is completely static in the map. So, when something is described, an object on the map is what is described (what you interpret about the object), not the object itself. On your map, trees and rivers don't change, you can use the same map for years, and still consider it valid, although the terrain could have changed a lot.
So, knowledge gives the impression that things are static, although they are not. Knowledge is an abstraction of the world, like a map is an abstraction of the terrain.
That's why you can describe a thing. This is not a paradox, it's just the way the mind works. But it is certainly a fallacy, I would call it fallacy of statism: things are perceived as being static, but they are in constant change.
What was described above is a large simplification of profound epistemological and philosophical debates centered around metaphysical idealism (the view that says that things don't correspond to what our perception indicates), perhaps at its best expressed by Immanuel Kant as Transcendental Idealism on his Critique of Pure Reason, where he does not only affirms that the thing-in-itself (what exists out of our minds, the noumenon) is not the same as the fallacious object we perceive (the thing as we know it, the phenomenon), but that even space and time are subjective constructs that give the world its shape.
A different problem: quantum mechanics:
A different issue is the specific description of quantum mechanical entities. As it's known, a photon can't be directly observed, because the light itself that our eyes need to observe it is made of photons. What we call "observation of a photon" is usually interacting with it, it's like throwing rocks to a specific rock in order to know it. And evidently, interacting with the proton changes it. But that's not a fallacy. You are not describing a specific photon when you destroy it in order to know it, but the generic object photon.
Evidently, if you throw small rocks to a big rock of type X, and the big rock breaks in two parts, the big rock does not exist anymore. But the description is not useless, now you know it, and it's kind, and now can create scientific knowledge, for example, "Rocks of type X are fragile".