Satisfactory

In some cases, it can actually be smart to underclock. It's exponential in that direction too, meaning machines become more power-efficient the more you underclock them.

Generally speaking, the only things you should be overclocking are resource extractors to be able to feed more production from the same nodes; overclocking production machines doesn't really make sense when you can just build more machines, space is pretty much the least limited resource in the game.

That said, there are exceptions and sometimes a little overclocking helps things balance out without weird machine counts that are hard to plan for, or if you just misplanned a space and expanding would mean tearing a lot out and redoing it