The most frequently encountered Magento 2 cron issues include:

• Cron not installed: You must run bin/magento cron:install --force as the file system owner to register the crontab; skipping this step means no jobs will ever execute.
• Missed or stuck jobs: When cron is misconfigured, indexes fall behind, transactional emails stop sending, currency rates freeze, and the cron_schedule table fills with pending jobs, causing stale product prices and broken catalog search.
• Duplicate execution on clustered servers: Running the crontab on multiple nodes simultaneously causes duplicate job processing and database lock conflicts — cron should only run on one node.
• Output suppressed errors: Redirecting cron output to /dev/null hides fatal errors and makes debugging nearly impossible.
• Cron running twice requirement: The bin/magento cron:run command must be run twice — the first time to discover tasks, and the second time to execute them.

Using a Magento 2 Cron Scheduler Extension helps surface these issues via a visual dashboard without requiring direct server access.