Efficiency vs effectiveness
Source: http://www.digital-knowledge.nl/dikn/en/to-develop/to-change/efficiency-versus-effectiveness.html
Change is often difficult; sometimes it's not. Sometimes it's just a matter of looking at things differently. In our society efficiency is seen as very important, but should we really make efficiency that important? Perhaps by using slightly different, but very similar measures, the nett result is really different!
The terms effectiveness and efficiency are related. Efficiency describes the nett use of resources required to perform a task; effectiveness refers to the degree a goal is reached.

Efficiency is a measure of the way something functions, as seen from the point of view of that thing or …show more content…
First of all if you look for both terms in most dictionaries you’ll find very similar definitions (which makes the matter even more confusing). Some dictionaries get it right, however. Here is the definition from Dictionary.com, which I like:
Effective (adj.): Adequate to accomplish a purpose; producing the intended or expected result.
Efficient (adj.) Performing or functioning in the best possible manner with the least waste of time and effort.
If you want an easier way to memorize the difference, remember this sentence: “Being effective is about doing the right things, while being efficient is about doing the things in the right manner.”
Let’s use a practical example to illustrate the concepts. Suppose that two guys, Mark and John, are trying to change a flat tire on their cars (each one has his own car).
Mark starts by taking out the jack and placing it under the car. He quite doesn’t know where to position it, so he goes by trial and error and wastes a lot of time doing it. After 20 minutes he finally manages to fix it, so he proceeds to lift the car and change the tire.
As you can see Mark was doing the right thing, but he was doing it poorly. We can say that he was being effective, but not efficient.
John, on the other hand, starts by grabbing a towel and cleaning the tire. He wants to make the thing shiny before he changes it. And mind you he is very good and fast at cleaning every little detail of the tire.
We