Why should we try to be a better person
Why? Is it because if we don't try, we drift to worsen? What defines what's better or worse? Is it subjective? Cultural? A social construct?
Assuming the meaning of life if to enjoy it, the better we are, the better the opportunities to enjoy it will be.
For example, let's take sleeping all day long; we can argue that's something enjoyable and thus a good thing to do, but by doing it in excess, we would miss chances to do something else. In this case, not sleeping all day would make us better. What if, we insist, that sleeping is what we want to do. In that case, that wouldn't be a problem and would be the rare case of someone who found what they want to do for the rest of their life. The reality, however, is not that simple. We need to do something else (go to work to buy food, make food, eat, etc.).
That's why good habits, like sleep well, healthy food, exercise, among many others, are deemed as good things as they enable us to enjoy life better, a healthy, well-slept body will enjoy a sunset better than one with sleep deprivation.
When we become self-sufficient, we enable ourselves to give us more opportunities to enjoy life (making yourself your favorite food is an example).
That's why I think we should try to be better persons because, in the end, it benefits ourselves. It seems so obvious isn’t it?
We don't get better overnight though it takes time to develop these skills and habits, hence the improvement is always an ongoing gradual process. There's no rush, but there's no reason to delay it either.
More often than not, the things we do to be better are also themselves the reward to enjoy life.