Glossary
XML Sitemap
An XML sitemap is a file listing the URLs on a site that you want search engines to know about, with optional metadata such as when each was last modified. It aids discovery; it does not guarantee indexing.
Glossary
An XML sitemap is a file listing the URLs on a site that you want search engines to know about, with optional metadata such as when each was last modified. It aids discovery; it does not guarantee indexing.
Listing a URL tells a search engine the page exists and that you consider it canonical; it does not oblige the engine to crawl or index it. Pages absent from the index despite being in a sitemap are a quality or crawl signal, not a sitemap problem.

Sitemaps listing redirects, noindexed pages, or URLs that canonical elsewhere send contradictory signals and reduce the trust placed in the file. A sitemap that disagrees with the page's own directives is worse than no sitemap.
For a small, well-linked site it is good hygiene rather than a lever, and generating it from the content source keeps it honest automatically.
No. It helps pages be discovered, which is a precondition for ranking, but it carries no ranking weight. A page listed in a sitemap and still unindexed has a quality or crawl problem.
Redirects, noindexed pages, non-canonical URLs, and anything returning an error. Each contradicts the page's own directives and reduces the confidence placed in the whole file.
An XML sitemap is a file listing the URLs on a site that you want search engines to know about, with optional metadata such as when each was last modified. It aids discovery; it does not guarantee indexing.