What does the System Recommendations tool do in Solution Manager, and how often should critical systems be checked?

It lists the Notes and patches available for a system, so you can proactively apply the latest security, performance, and legal corrections.

Check critical systems monthly (at minimum quarterly). To configure: in managed system configuration go to step 5 and tick Enable System Recommendations, then step 8 → Apply Settings, and ensure the SM: System Recommendations background job is scheduled.