How long will my post remain visible on the timeline?

How long will my post remain visible on the timeline?
That depends on the settings you give to the post.
This can be done in two ways:

1. On timeline
2. With findability.
Learn more in this article.

Organized timeline
Each new post on the timeline contains a colored bullet in the upper right corner. 
When the post is read, this bullet disappears. Thus, the disappearance of this bullet means the post is considered read and is gone from the timeline the next day.

Why do read posts disappear from the timeline the next day?
Basically, the basic principle is to keep the timeline as empty as possible. This way, the timeline remains clear and the AppLearning is the focus. Otherwise, the AppLearning may get hidden between all kinds of posts and compliments. Thus, it is not possible to "pin" posts to the timeline.

In short, by making the AppLearning central, we encourage employee development.

However, there are ways how you can make posts return automatically more often. 
Learn more about this in this article.