I learned about the equilibrium constant. Now, I've seen that the equilibrium constant of burning is extremely small $(K \ll 1)$. here, I have a question. you see, $K$ is still NOT 0, which means that the forward reactions happen at least a tiny bit. Then, shouldn't we see some parts of anything burning at least a little bit?
shouldn't I be able to observe this tiny bit of combustion happening at room temperature? if $K$ is extremely small but not 0, I don't understand it.

In general, I've always wondered why we don't see small amounts of reactions happening spontaneously since the equilibrium constant isn't 0.

There's the concept of a "threshold energy", but it seems a bit arbitrary and not well-defined.
but I don't. Am I misinterpreting $K\gg 0$ or missing something?

No, you are not misinterpreting the concept of an equilibrium constant or missing something.

The fact that $K$ is very small for the combustion reaction does indeed mean that the forward reaction happens only to a very small extent in comparison to the reverse reaction, which is why most substances do not ignite spontaneously under normal conditions. However