Complain ?

I think it’s natural for people to complain. Everyday we’re faced with a lot of reasons to complain: they shouldn’t be doing this they should be doing that, it shouldn't be this much, shouldn't be this little, etc.

Having the occasional complaint is fine. To expect a life without complaining (by you or others) is unrealistic.

Lack of empathy leads to complain. A lot of times we complain because we lack empathy for others. Think about this: You complain that someone isn’t getting things right, they should be doing it this way because that’s what we would do if
we were in that position. When we lack empathy we aren’t able to fully put ourself in the other persons place. We don’t know the thoughts going through their head or what other complexities they are facing in their lives as at that point in time.

Some people are just genuinely unhappy. They will refuse to find joy in any/every aspect of their life and when you do so much to please them you'll end up being the source of their unhappiness. Genuinely unhappy people will settle for a complain as a measure to express their dissatisfaction with their life and in many situations it’s used as a coping mechanism as well. Always remember that life is not a race for material things be grateful always.

Complain today and complain tomorrow leads to tiredness
Tiredness kills the spirit of going on
Tired today and Tired tomorrow leads to fed up.
Fed up leads to laziness; laziness to being stagnant then to unseriousness which will eventually lead to RESIGNATION

Solution
Be grateful, be constructive when expressing your dissatisfaction and change your perspective. Turn that energy into something positive.