How important are breadcrumbs? I understand it is important for navigation but I'm not certain how important it is for SEO? Are there use cases where breadcrumbs do not help SEO - and therefore is not worth the time to set up and maintain?
First and foremost:
You should think about satisfying the needs of your users. No SEO argument should stand in the way of providing them with the tools they need.
With that in mind:
Breadcrumbs do highlight important keywords for search engines but most importantly they act as secondary navigation and help users know where they are within a website structure. Below is a quick list of benefits to your users:
- Breadcrumbs show people their current location relative to higher-level concepts, helping them understand where they are in relation to the rest of the site.
- Breadcrumbs afford one-click access to higher site levels and thus rescue users who parachute into very specific but inappropriate destinations through search or deep links.
- Breadcrumbs never cause problems in user testing: people might overlook this small design element, but they never misinterpret breadcrumb trails or have trouble operating them.
- Breadcrumbs take up very little space on the page.
So, to answer your question:
Yes, it worth the time to set up and maintain.
I don't find the article I read which speak about this subject. But anyway, It says (from a Google employee) that they will reward websites for the user experience comfort more than technical guidelines everybody's following. And I think giving everything to the user is better (in business terms) than SEO (word of mouth, satisfaction, retention)