I agree, although most of the time you do end up needing to consider it with Map/Filter. It's just, it doesn't force you to. Which means either you think abou

I agree, although most of the time you do end up needing to consider it with Map/Filter. It's just, it doesn't force you to. Which means either you think about it later, or it bites you in the ass because you didn't consider the empty case. Not always—and for those cases where you don't end up needing the empty case, Reduce is probably not necessary, and Map/Filter is sufficient.