Welcome to the Q&A Forum

Totally Agreed... webmaster tool (now search console) gives the functionality to tell google about your site updates instantly using Fetch facility in the tool, so you can index your site's new or updated content as well you can find the errors on your web pages like crawl errors, indexing errors, and more. you can see the manual action as well if your site spreading spam on internet. and after fixing the issues you can send reconsideration request also. so, it is a big benefit for verified site in Google webmaster tool.

I agree with Gaston, but usually the SEO benefits that you will see are rather small. This was a tactic that was used a couple of years ago to just buy a bunch of domains that already have a ton of links to them and then just point them to your main root domain. Usually the easiest signal to look at is already to see if you suddenly start redirecting certain URLs to another page.

Thank you both @gaston riera and @peter nikolov