Nobody listens to a person who gossips i.e. speak ill of others behind their back. People become afraid that when they turn their back, immediately, similar ill will be spoken about them. Thus the speaker lose all credibility and not taken seriously.
people do not listen to a person who is negative always, people stop taking him seriously, believing that the person is in the groove of negativity–will go on and on, without a respite. Listening to such a person is sheer wastage of time.
Habit of Complaining is also not liked. Producing excuses for any failure, is also bad. Throwing blame on others for failures, loses respect of the potential listeners. Speaker loses credibility . Too many tall claims also can cause others to roll their eyes and tune you out –they just stop listening the speaker. Also, when someone insists their ideas are the only way things can be, this kills debate and the patience of others.
If you want to be heard, you have to be honest, stand on truth, be your word, and wish people well.When you have all these, you need not raise your voice or cry hoarse, you will automatically lower down your voice. People will come to you to listen even without invitation, they will believe everything you say.