Does automation allow marketers to be more effective with their time? Why or why not?

The "yes" answer to this is especially if you live in a different part of the world than your target audience. In my case, I use an app to tweet at a certain time-frame. The "no" part is that when it is automated, the tweets can be very mechanically produced, just as if a bot wrote them, and they make no sense. It becomes "posting for the sake of posting" rather than really helping your audience with useful, authentic information.