I always confuse the both since they sound so similar: Being effective and being efficient. In casual conversations, both get used seemingly analogous without thinking twice about it. Even a thesaurus lists both as synonyms.
But we are missing an opportunity here. Let’s first get the semantics sorted:
Effectivness is doing the things that get you closer to your goals. Efficiency is performing a given task (whether important or not) in the most economical manner possible. Being efficient without regard to effectiveness is the default mode of the universe.
Timothy Ferriss in The 4-Hour Work Week
They seem very dissimilar now, don’t they?
What it all comes down to is that we, as obedient worker bees get ourselves busy so we drive our goals forward. We are very efficient. To a point where we are so busy that there is no time left to stop once in a while and evaluate if we’re doing the right thing ( being effective).
This seems such a good way to slow down progress that even the CIA used it in a manual on how to sabotage corporations and production:
From now on think about it like this: What you do is way more important than how you do it. Don’t get me wrong. Doing your tasks efficient is still important but dwarfs in comparison to doing the right thing.