Due to the nature of render farms, frames get broken into segments to be rendered by multiple computers. The best way to do this is through batch rendering which means each node is assigned a frame one at a time, but not necessarily the next frame in the sequence.
The benefit of this is that we can assign many computers to work on your animation simultaneously. The only issue is that each node doesn't know what was calculated on the previous frame.
Certain elements, like dynamically calculated particles, need to be baked so that each computer knows what will happen next and render the exact same thing.
By baking as many aspects of your animation as possible, you are limiting the number of possible errors that may pop up. Also, when an error does appear, it reduces the number of things we have to investigate speeding up support.