Why does most garbage tend to smell the same?

Factual Questions
1

Is it because of similar contents in the garbage, or is there a bacteria or something that gives off the telltale garbage scent?

2

WAG: a bit of both? The stink is from rotting vegetation and meat for the most part. Without food waste, our garbage doesn’t stink.

3

Ashes to ashes, dust to dust, and all garbage to the same uniform sludge. I would guess that the end products of the bacteria causing the rotting are about the same no matter what organic material you started with.

4

I’d say that the similar stink is because the same bacteria and fungi are at work and they emit the same stinky chemicals.