This is not a rule but a timely advice to newbie who wants to keep their posting reputation in good standard.
One meaningful post is better than 15 to 20 post that are low in quality just to fulfill signature requirements.
You have a very good advice. There I no need to rush in ranking up and joining a signature campaign. Because this could lead to some mistakes which will be costly. It is better to enjoy the forum and grow naturally.
Are there guides to making quality posts??
This link might help you to know more about posting.
https://bitcointalk.org/index.php?topic=1689727.0. Quality posts are contributions that are beneficial to the community. When you can give out helpful information that educates, solves problems or answers questions, you are a quality poster. For me, the easiest way to become a quality poster is to keep learning and through observation. You would be able to contribute meaningfully to the forum if you keep researching. And by observing reputable members, you can easily learn from them.