I noticed this behavior also when I was following Googlebot's crawl of my old pages after I had done a redesign. it's not because of sitemap or because of url

I noticed this behavior also when I was following Googlebot's crawl of my old pages after I had done a redesign. it's not because of sitemap or because of url structure or because of dynamic content. Mine were blog articles in the same format. This is how it was crawled: sitename.com/year/mo/day/stub sitename.com/year/mo/day/stub-one sitename.com/year/mo/day/stub-one-two sitename.com/year/mo/day/stub-one-two-three sitename.com/year/mo/day/stub-one-two-three-four