# In Markov Decision Processes, why does R0 get skipped?

I'm in the process of learning the MDP, and a pretty small thing is bugging me. Everywhere I look, I see the order of things go in this order:

$$S_{0}, A_{0}, R_{1}, S_{1}, A_{1}, R_{2}, \ldots, A_{t}, S_{t}, R_{t}$$

My question is, why did $$R_{0}$$ get skipped?