Clarify the point about keeping pages in the DOM

**URL**
https://ionicframework.com/docs/react/lifecycle#react-lifecycle-methods

**What is missing or inaccurate about the content on this page?**
There are such words in this paragraph:

> componentDidMount fires the first time a page is displayed, but if you navigate away from the page **Ionic might keep** the page around in the DOM

Can anyone please clarify what does 'might keep' mean? When does Ionic keep the page in the DOM and when doesn't? Can
Ionic remove already kept page from the DOM?