Here is the simple breakdown:
1. Boot Mac from a powered off state.
2. Launch Outlook
3. Observe that Outlook connects and syncs
4. Put Mac to sleep
5. Wake Mac
6. Observe that Outlook is in "Not Connected" state

7. Select menu option Tools > Send & Receive > Send & Receive All

8. Observe that Outlook is in "Not Connected" state

9. Close and relaunch Outlook

10. Observe that Outlook connects and syncs

This happens to everyone I know, not just at my company. Hundreds of man-hours are wasted on this. Lots of embarrassment comes in the form of, "I'm sorry I didn't get it, I didn't notice that Outlook needed to be restarted."