Pedro Dias's post reminded me I read an excellent article he wrote recently, and it says something I've felt for years but he puts it much more articulately. The gist: it's so common for people to build websites or make changes to websites with zero SEO involvement, and then loop in an SEO person after the fact to "do some SEO on this" or "address any potential SEO issues" once the damage has been done. It's wildly inefficient. SEO input needs to be present from the start, baked in.