Google has bots and spiders which crawl your website and take screenshots each time they do, changing and improving or declining ranks of your pages within search engines based on the last crawl.
So you may be asking yourself why is the google cache date so important?
You see, when you change or update your website, you will always need to wait 2 weeks after the last cache date crawl to determine if your changes had a positive or negative effect on your rankings/website.
How can you find out when your website was last cached?
SEO quake is a free SEO plugin that you can download, by clicking on the SEO tab which appears in your toolbar. You simply go to your website and click on the SEO Quake tab and it will show you the cache date of each individual page you currently view on your screen.
Toxic backlinks detox and cache date are like bread and butter.
When webmasters and SEO agencies run through backlinks and detox any bad toxic backlinks, they will usually block 15 to 20 toxic backlinks at a time and run them through a google disavow.
The google cache date plays a huge role, the SEO agent or the webmaster will know that after the website is last crawled (the cache date) they will need to wait 2 weeks to see the results of their changes to removing the toxic backlinks.