Breadcrumbs show users where they are on your site. Google loves them. They get displayed as rich results in search — a nice path under your title that makes your listing stand out.
Add With JSON-LD
One script tag in your header. Google does the rest. WordPress plugins like Yoast add them automatically. Custom sites need manual JSON-LD.
Worth the 10 Minutes
Not a huge ranking factor. But the rich result makes your listing more clickable. More clicks = more traffic = better rankings. Snowball effect.