I am unable to sync color categories from Outlook. Why?

Please note that iCalendar syncs with Outlook through the stock Calendar app. Thus, iCalendar will display Outlook events exactly as the stock calendar app does. It is known that stock calendar app has some limitations on the color choice for events. For example:

1. An event created on Outlook with a specific color is not guaranteed to be displayed in the same color on the stock calendar and iCalendar

2. An event created on the stock Calendar app or iCalendar with a specific color is not guaranteed to retain its color when it migrates to Outlook.