"Why to speak true?"

One of my uncle always asks for all people, "Why are you not speaking true ?". They always insist for speaking true(NO MATTER WHAT).I also started thinking and I got very basic funda.

How 1 lie can lead you to Failure.

Suppose you are learning some thing from your teacher and teacher ask you , "Do you understand what I am saying? "
We answer it as "Yes" (Though we fail to understand ) , teacher goes to next level.Then we start facing
problems (Because that 1 lie created us incapable to learn some thing bigger) when we face the problem at that level, we again start lying.... Ultimately we never achieve and we never learn the things

So 1 small basic principle "speak true" can lead us to great achievement.

Also when you start speaking true, it is automatically start accepting the failures, and when you accepts the failure points then you have a space to find solution on your failures , if you have not accepted that you are fail, how can we improve and become successful?


After thinking on same line -- I observe that , In schools also , when teacher teaches to 50/60 students, and finishes one topic, they asks "Do you all understand ?" answer from whole class is "YES " , actually it the only 10/20 % student , who actually understands it , but all say "YES" (lying) , and there the problem starts.
which leads to failure in big exams ... and everywhere.