For a significant amount of people, there is an over tendency within the personality, to say "yes," almost without thinking about it, to issues in which with any reasonable reflection, a more reasoned or qualified response would have been seen as more appropriate. The main reason that so many of us say yes, in certain situations, is that we want to get along with others, we don't want to be seen as difficult, and thereby by saying yes, it demonstrates that we're a team player, even if in reality, we are not.
Each of us wants to be loved, and to love, so that there is an inherent bias to want to please and to placate others, in the hopes that, by doing so, the same consideration will be shown to us. While that may be true to a certain, modest extent, politeness, empathy, and listening, are not the same things or make up the same characteristics as acquiescence. It is said that one's "no", should mean "no," and thereby the corollary should follow that one's "yes," should mean "yes", and this further signifies that when one says "yes" but really does not mean it, that one has been false to one's self.
It is well understood that the easy way and the simple way in certain conditions is to say yes, because we often don't want to be the ones that are holding things up, and/or the ones that are rocking the boat. But in point of fact, if saying yes is wrong, and you know that, you have done yourself as well as the other a large disservice. Too many times we are afraid that we will lose someone, lose their respect, lose their friendship, and lose their validation, by not giving in to their demands or to their wants, but when these things conflict with who or what we are, it is our duty to stand up for our principles, and if by doing so, this means a breach between two parties develops, then perhaps that party was not so worthy of our respect and admiration as we previously thought.
It is important to get away from making snap affirmations to requests or to things, to which, the issues being brought up, required a more thoughtful or nuanced response. If you think back upon your own life, certainly it will be easy for you to remember many times, when you got your way, and many times when you did not, yet you know, for a certainty, that in hindsight, not all the times that you desired your way, would it have been prudent or the better path for you to have had that granted. This means in some cases in which you were absolutely adamant that you needed a yes answer, and did not receive it, this was, in fact the correct course of action, and now belatedly recognized by yourself as wisdom.
True wisdom comes not by going with the flow or by saying yes, without thought, but by doing right, as we are gifted in seeing the right, to which sometimes the best answer is not the easy one, but the more difficult and necessary one.