Google's John Mueller said Google will ignore redirect loops for search because redirect loops are broken. A redirect loop is when you have page A point to page B as a redirect and then you also have page B point page A. So you have them both redirecting to each other and it goes on an infinite loop. Browsers cannot handle them and no do search bots want to handle them.
Here is John's tweet:
It's always good to fix broken links for your users. In general, a redirect loop is a URL that doesn't work, so it's essentially a broken link. We ignore these for search, but again, it's always good to fix broken links for users.
— 🍌 John 🍌 (@JohnMu) July 23, 2019
Here is what some browsers look like when you serve them a redirect loop:
So yea, don't do that to your users, browsers or spiders.
Forum discussion at Twitter.