Truthfulness is not just about being truthful towards others, but it's also about being truthful towards oneself. Those who can't even be truthful towards themselves, how can they be truthful towards others?
Due to intense egoistic attachment, identification, desire of craving and aversion, and expectation towards the qualities of names and forms in themselves, people who have certain things that they don't like about themselves will also have the tendency of being untruthful towards themselves.
There are many unnecessary personal and relationship 'problems' in people's life is due to either people rather playing mind games of 'politeness' and 'appropriateness', than being straight to the point about what they want and don't want, or people are afraid of being truthful, as they are afraid of 'losing' something that they don't want to loose, if they are being absolutely truthful.
People are afraid of "Expressing their thinking or thoughts, as it is," as they are afraid of their thoughts and ideas about certain dissatisfaction and disagreement towards something or someone would be offensive or upsetting for other people. Or, people never want to be straight and firm about, "This is what I want or don't want," most probably it's because they themselves are not very sure of "That is really what I want or don't want."
Certain cultural and social values and practice don't like truthfulness and straightforwardness in all kinds of relationships and dealings with other people in everyday life, with the intention of "Don't want to offend or upset anyone." Where truthfulness and straightforwardness is being seen as a form of 'rudeness' and 'inappropriateness', and even worst, as a form of 'offensiveness', in the world of hypocrisy, pride, image and reputation.
Some people rather not to hear or know the truth that they don't want to hear and know. "If you are going to tell something that is not nice about my children, then I don't want to know about it. I am a good parent. I taught them to be good, and only be good. They will always be my good children, as long as I don't know anything bad about them." It doesn't matter what is the truth about their children, more importantly, it's about protecting their desired good reputation of "I am a good parent who proudly brought up my children to be all good and nothing bad," as well as, protecting their desired good image of their children of "I love my children as long as I don't know anything bad about them. Don't spoil my love for the good image of my lovely children who are all good and nothing bad."
People think that this 'politeness' and 'appropriateness' will help to make everyone's life easier and lead to more peace and harmony in all kinds of family and social relationships, or make the world a better place, however, it doesn't. It only leads towards further unnecessary problems as well as wasting everyone's time and energy. It also empowers the ignorance and egoism in all and everyone, by very carefully 'protecting' the easily be 'hurt and broken' minds under the influence of ignorance and egoism.
They want to be 'nice' to everyone, however they themselves might be suffering from great mental and emotional disturbance due to they are not happy with certain things that involve other people, but they refuse to express their unhappiness, or disagreement, or what they want and don't want, while holding up and accumulating those unhappy thoughts and feelings, causing mental and emotional imbalanced in themselves.
If people know how to let go, without holding up all kinds of unhappiness or dissatisfaction towards this or that, then that's fine. There's no problem.
Those who can't let go but keep holding up, until a point that they can't hold any more, and they will 'explode', causing more serious 'damages' to oneself and others.
Not only yoga practitioners, but human beings need to learn how to handle all kinds of truthfulness and straightforwardness that oneself might not like, desire and agree with, without being disappointed, offended, upset, hurt or disturbed by something that oneself doesn't like, doesn't desire and doesn't agree with, in all kinds of human relationships and dealings.
Those who would be disappointed, offended, upset, hurt or disturbed is nothing but due to ignorant egoistic attachment, identification, desire of craving and aversion, and expectation in themselves, towards oneself and others.
The minds that are free from attachment, identification, desires of craving and aversion, and expectation towards themselves and others, they don't need to be untruthful about anything. They can choose to express or don't express their thoughts, ideas and opinions, as they are, but there's no need to be untruthful by expressing something that is not what it is (telling lies or white lies), or only expressing something that everyone would like, desire and agree with. There's no fear of losing something. There's no desire of pleasing anyone for any reasons. Healthy minds don't need to be pleased by anyone. While how everyone reacts towards other people being truthful about their thinking and feelings about something, it's their own freedom and responsibility. Everyone are free to think and feel and react in the way that how they want to think and feel and react. There's no disappointment, offensiveness, upset, hurt or disturb upon coming in contact with all kinds of names and forms that are not necessarily pleasant, desirable and agreeable.
It doesn't mean that one should not move away from certain conversations or dealings that involve abusive and violent behavior, and be attacked and abused under such circumstances. One can move away from energy wasting conversations and dealings that involved abusive and violent behavior, while not being determined or disturbed by others' ignorant behaviors, actions and reactions deriving from ignorance, or mental illness, where the minds don't have correct understanding, reasoning power, clarity, awareness and self-control.
Peace and harmony in the world doesn't mean that there's completely no disagreement or dissatisfaction among one another, where everyone should like and agree with one another, where everyone shouldn't and won't express any thoughts, feelings, ideas and opinions that some others might not like, desire or agree with, while only express thoughts, feelings, ideas and opinions that everyone would like, desire and agree with.
The world of diversity cannot advance or 'grow' towards a healthy state of true peace and harmony, unless the minds are free from egoistic attachment, identification, desire of craving and aversion, and expectation towards oneself and others, while respecting everyone being what they are, as they are, being different from one another, having different thinking, feelings, ideas or opinions about many things, without generating resentment or offensiveness towards others who are different from oneself, who have different thinking, feelings, ideas or opinions towards oneself, and towards all and everything in the world, that oneself might not like, desire or agree with.
Those who would feel disappointed, offended, upset, hurt or disturbed by those whom oneself loves very much, but they don't love, or stop loving oneself, is due to ignorance and egoism.
"I am so loving and kind to you. I did so many things for you. Why are you so ungrateful, unappreciative and unthankful for it?" This is a common reaction that indicating this mind itself is under the influence of ignorance and egoism, and doesn't know what is love and be kind, or how to love and be kind. They will have to take their own pace and effort to realize the ignorance and egoism in themselves.
Those who have correct understanding, who are free from the influence of ignorance and egoism, who know how to love oneself and all and everything unconditionally, will respect everyone's thinking, feeling and desire of want and don't want, as they are. Respecting all kinds of impermanent changes as they are. There's no disappointment, resentment, hurt, or painful sorrow in such minds.