When a lot of drivers in a specific area set a destination, it limits the number of drivers that are able to accept trip requests from all riders. This causes longer wait times for both drivers and riders.
In order to make Uber a reliable transportation option, we will have to limit the number of drivers that can use this feature in the busiest areas and times of the day. During these times you may receive a notification that the feature is unavailable at the moment. If you receive this notice, please note that it is only temporary and the feature will become available again at a later time.
If you are not receiving a notification stating that destinations are currently unavailable, you may not be able to use the destination feature due to reaching the daily limit. You are able to set your destination twice daily. Every day at midnight, your available destination count will reset. If you have unused destinations on a given day, they will not carry over to the next day.
You can always check how many Driver Destinations you have remaining for the day in the app menu.