Well, why shouldn’t we? Surely, we often know better. Or we think we're smarter. Or we have expertise or experience in a certain field and the other person doesn't. Or we're simply well meaning and believe that's what friends and family do - if we love another person, we should tell them what to do in certain situations.
All this sounds way too familiar, and yes, I'm also guilty of telling others what to do. And if my friends and family disagree and dare to say something, we start an argument. Why? It's very obvious: we defend our position and argue back, because our egos are hurt. We feel unloved, unappreciated, not listened to, not respected.
Now, it seems that a more reasonable approach would be - before we open our mouths to tell others what to do - to stop and question ourselves: why are we doing this in the first place? What's our own motivation? Not counting here situations where people’s actions directly hurt others and someone really needs to tell them to stop and think what they're doing.
If we care to look at our own motivation, it’ll always be some kind of ego-driven need, which always makes us weaker and open to manipulation from others.
Is it pride, eg we think we know better?
Is it desire to satisfy our own needs, eg in which case it’s direct manipulation?
Is it victim mentality, eg fear that if others take a course of action undesirable to us, we’ll become unhappy?
We all have egos, some gigantic and others much smaller, so what's wrong with having ego-driven needs? Well, I see several problems here and all of them eventually lead to conflict and unhappiness:
1. Ego-driven needs make us, our happiness, our life, depend on what other people say and do.
If only that person does what I want him to do, then I’ll be happier. This mindset makes us and our moods depend on others. Yet people are very unpredictable - they change, their preferences change, their interests change, their life circumstances change, etc. Why depend on something so changeable and that we can’t really control? This brings me to the next point which is...
2. We can't control other people.
And yes, I'll repeat that: we can't control and change other people. If other people aren’t motivated to change, there’s only so much we can do to drive them, push them and manipulate them into changing. And why would we do that at all? So much energy put in the wrong place at the wrong time for the wrong reason. So little energy left to work on our own personal growth, positive attitude to life and happiness.
3. We come to this world to make ourselves better humans.
We’re responsible for our own personal growth, not the personal growth of others. Yet I'm not saying here that we shouldn't lead by example. Many people start believing that something can be done only if they see that someone is already doing it. What I'm saying is that we should give others excellent examples of good ways to do things. And I'm saying 'good' ways to do things, not the 'right' ways. Because there's no right or wrong way to do things.
4. There're different ways to do the same thing - it's all about embracing diversity.
In fact, we sometimes become so stuck in a particular frame of mind or a particular way to solve a problem that we miss other opportunities, solutions and perspectives on life. We become literally blind to anything new in life. Well, that's exactly why it pays off to shut up and listen to another person's point of view, even if this point of view just doesn't seem to make any sense at first.
5. We shouldn't deprive other people of opportunities for experience and growth.
Other people have the right to receive different experiences in life and learn from these experiences. Hopefully, this will bring them closer to becoming better human beings. If not - well, people have free will and they can use it not to learn from their experiences. Or to make wrong choices. Or to get stagnated. Or whatever they decide to do with their lives.
It might be very tempting to make a person immediately jump to the right solution, especially if this solution is very obvious to us (even if we're blindly and stubbornly convinced that our solution is the only right magical solution). Yet, if the person hasn't experienced why this solution should be the right one and what will happen if they make the wrong choice, then how would this person know what's right and what's wrong for them? Worse, what's even the point of living a life if you're expected to blindly follow someone else's advice? By depriving other people of choice to make mistakes we deprive them of their lives and personal growth.
To sum it up, I'm a strong believer of personal choices and the right to make mistakes in life and learn from these mistakes. I believe that time spent on my own personal growth - as I see it at this point in time - is time well spent. I also believe that I sleep much better at night when I don't take that extra heavy unbearable responsibility for trying to make other people better.