My entry does not appear on the site
Almost always one of three things: the entry is not published, the site was never granted access to that collection, or the site is showing a cached copy. Check the entry's status first — it is the cause in most cases — then the site's per-collection permissions, then caching.
Requirements: access to the collection in question, and — for the second and third checks — a role that can manage website connections.
You added an entry, it looks right in the CRM, and your site does not show it. This is one of the most common things to run into, and it is nearly always one of three causes. Work through them in this order — the first accounts for most cases.
1. The entry is not published
Every entry carries a status, and only published entries are meant for the public. An entry left unpublished is complete and visible to your team but deliberately invisible to visitors — that is the whole point of the setting: you can prepare something fully before the world sees it. Fix: open the entry and publish it. If you use a publication date, check that too — an entry scheduled for next week will not appear today.
2. The site is not allowed to read that collection
A connected site is granted access collection by collection. If the site was set up to read your products but you have since added a new collection — services, say — the site has no permission to read it, so the entries never reach the page even though they are published. This is easy to miss precisely because it is not an error you see anywhere; the collection is simply absent. Fix: open the website's connection settings and grant read access to that collection.
3. The site is showing a cached copy
Many sites cache their pages for speed, and a cached page keeps showing what was true when it was built. If the entry is published and the collection is granted, but the page still looks stale, the page has probably not been rebuilt or its cache not cleared. Fix: clear the cache or trigger a rebuild on your site. If this happens often, have the site rebuild when data changes rather than on a fixed schedule.
Still missing?
Two less common causes are worth a look. If the entry is filtered out by the page itself — a category, a date range, an "in stock" condition — it may be published, permitted, and fresh, yet excluded by the query behind the page. And if a required field the page depends on is empty, the site may be skipping the entry rather than rendering it half-built. Check the page's own filter before assuming the problem is in the CRM.
Related
How a site reads your records is covered in using Sonta as your site's backend, and what publishing actually controls in the data model.