Database collisions: If both environments take orders simultaneously, pushing staging overwrites live orders. Note the highest order ID before pushing and verify no overlap after (see section 3.8).
Payment credentials: Staging uses test credentials. They come with the push. If you don’t switch to live, the store appears to work but no real payments process. This is the #1 post-launch emergency for agency builds.
URLs: Staging has a different URL. Use proper search-replace (WP-CLI or Better Search Replace) and verify siteurl and home options.
Subscriptions: Verify staging mode is active on staging, deactivated on production. Staging can process real renewals if not detected correctly.
wp-config.php: Contains environment-specific values. Either exclude from push or verify manually after.
Cron/Action Scheduler: Clear orphaned tasks from the staging environment after pushing. Check WooCommerce → Status → Action Scheduler.