Bounce Rate in Google Analytics

In other words, a page will always have a 0% bounce rate if it is not the first page the user views.
A 0% bounce rate typically occurs when viewing content only accessible within the website.
Having a 0% bounce rate is not necessarily an issue or problem.

2nd reason of a 0 percent bounce rate?
Did you know that you can have a 0 percent bounce rate even if a user left after only visiting one page?
Yup, when setting up Events, you can make Google Analytics (GA) count any Event hit as an ‘Interaction’ and

therefore reduce ‘Bounce Rate’ even if a user didn’t visit a second page of your website.