Why do we need a closure in the linking?

Question

Search Engine Optimization

Why is it necessary to close the linking and what will happen if this is not done?

Suppose I am going to write 100 articles and I will link from each new article to some old one, but what if I need to write more than 100 articles? How can I close this circle if I keep writing new articles all the time?
At the same time, I only need to promote articles, there is not much point in promoting sections or the main one. What do you advise?