How to tell if your website seo is bad
Slow site load time
Poor or no use of the Title tag - your homepage is called "Home" or titles that start with "The" or "Welcome" or using the same title on every page of the site
Poor use of SEO URLs, www.site.com/ID?=1337 vs. www.site.com/cool-toys.html
Lack of landing pages to target important keyword phrases
Keyword stuffing titles, meta tags, and site content
Any content copied from another site
Content duplicated within the site
Insufficient amount of relevant indexable content