For me one of the most eye opening concepts I have ever encountered is the 80-20 rule. If it's new for your I suggest to watch this: https://www.youtube.com/watch?v=1EI6Ph2x4gM or read Wikipedia.
Concentrating on the vital 20% and neglecting the rest is not an easy undertaking. However there are tools and methods to help you doing it like the Five Whys, Root Cause Analysis or Current Reality Tree. These tools help your to analyze the situation and to isolate the most critical factors. All you shell do to focus on these and work hard on them, the result is secured.
I have used these tool in several occasions and they were always leading me to the critical factors. Attacking these factors with determination helped to achieve good results at least on the sort run, but not in any case on the long term. Why? Have I made a mistake (I certainly have made some...)? And why have I still the feeling of uncertainty about the these methods? Is it my strong cultural roots which tell me that more efforts lead to proportional more results? Or is it something else?
A military strategist would tell you that attacking the enemy at it strongest point if successful will almost certain lead to victory but the price for it will be immense and so will be the possibility of failure. You should think it over.
I think you have to be careful with the 80/20 rule and its relatives. Maybe you have found the root cause, or the constraint or the answer to the fifths why, and yes eliminating/solving/controlling it would bring the best results. Still there are other factors to consider:
- The cost: maybe the vital 20 percent will cost you 5 times more (in time, money or stress - you name it) than the 80 percent.
- Some things maybe minor but must be done. Don't forget about them.
My suggestion make a list of factors and weight them on their effect (use the 80/20 rule) and the weight them again according the effort (time, money, nerves - depending on your situation). This double weighting will tell you what to do fist. And if you have done it (or failed :-( ) do the analysis again and make a fresh start. Until you found that doing nothing (i.e. something else) is the best option.