4 Answers

 b/c some people don't want to listen to logic and reason. Or, they defy it.

Logic and reason are limited. Logic is purely man made and reason is merely a theroetc composition of  justifications that are increasingly divorced from reality by secrets or hidden agendas. What is true is open, clearly understandable and readily available for anyone to know and understand. Thus the problem. Logic and reason are used to tear truth apart into smaller and smaller bits and pieces that can be manipulated for some reason…such as greed. We see this in the legal systems of our Government. Here, in the US, congress would answer the issue of homosexual behavior by tattering permissiveness into 10,000 separate issues requiring years to slog through as a form of job security. Being responsible for doing nothing. No wonder the Republican congress is dragged along on Obama’s coattail. 

This same oddity of our time is how our educational system uses every device imaginable to divide subjects incrementally into thousands of other logically and reasonable seperate subjects of extremely fine detail requiring years of boring lectures to bake an apple pie.

Sometimes it's a simple matter of common sense. If someone lacks common sense, all the logic and reasoning in the world will fail with them. Just my opinion. 

^Logic and reason don't fail to explain the truth. It's just that they are only a part of the explanation, but  a large part. The critical thing here is to define the truth as it pertains to philosophical differences. For example, are we talking about science, mathematics, and definitive subjects that can be quantified. Or are we talking about things of a more spiritual nature which tend toward the intuitive and mystical and are almost impossible to quantify, such as  peace, love , and serenity,  things with more of an emotional appeal. Religion falls into this category. Many try to use logic and reason to deny religion and it does have a strong appeal to the science minded. However, as much as you try to denigrate or disprove religion it is still spiritual and has a strong influence on people and is therefore real. The qualitative is sometimes hard to measure, but real never the less. I myself am not religious because logic and reason does disprove much of religion, but the spiritual survives. I remember reading that logic and reason might be able to disprove 99% of religion but there would always be that 1% that defies reason and must be taken into consideration. And that is why defining the truth is specific rather than broad. It must be defined constantly.