Excel solves this right problem, and Erlang does not. Erlang allows you to create concurrent programs, i.e.: programs where the result is schedule dependent.

Excel solves this right problem, and Erlang does not. Erlang allows you to create concurrent programs, i.e.: programs where the result is schedule dependent. One right problem is allowing people to write deterministic parallel programs. This gives you the speed (from parallel) with the reliability (from deterministic).