Never say never, never say always...
Like everything else in Poker, it all depends, there are no absolutes. I think it depends on the player your playing against, the previous action on previous streets, and what you put you opponent on. So, sometimes a raise is good, and other times it would not be. There is so much information available, or lack of information that making the perfect decision all the time is impossible. Just make the best decision you can with the information you have at that moment and hope for the best. Constantly adjust to the situation, or make your opponent adjust to you.
Good luck.