It amazes me how few people either know about the 80/20 Principle (sometimes called the Pareto Principle or 80/20 Rule) or how few people will apply the prinicple to their daily lives. Here's a quick explanation:
The 80/20 Principle/Rule/Mindset states that a minority of effort will usually lead to a majority of results. Seems pretty easy, right? I mean, just be reading the sentence you probably thought of instance of when the rule is true. If you sat back from the screen, you could probably think of many cases in which the rule is true.
Does it always have to be 80 and 20? No. But 80 and 20 are good illustrators of the ideas of small inputs providing huge results. Does this scare you? Maybe it should -- obviously you don't think this way about everything. For you I suggest reading "The 80/20 Principle" by Richard Koch, you can get it here at Amazon. Look at that! By spending a small amount of time on my very small site, you get to save yourself all the work of finding this book because I've done it for you. That small input of my site into your browser yield the majority of rewards!