Why updates go wrong
Most update failures come from compatibility conflicts between plugins, themes and the PHP version on your server. Updating everything at once on a live site makes it hard to identify the cause.
Back up first — and verify
Take a full backup of files and database before any change, and confirm it can be restored. A backup you have never tested is an assumption, not a safeguard.
Use staging
Apply updates on a staging copy first. Review changelogs for major version changes and test them in isolation.
Regression test what matters
After updating, check your homepage, key service pages, navigation, contact forms and any checkout. Submit a real test form and confirm the notification arrives.
Document the change
Record versions before and after, what was tested and any issues found. This makes future troubleshooting far faster.