Why Sandbox projects don't have a minimum time of requirement before to try to move to incubation ? I see that Harbor joined as a Sandbox project on July 31 and just after 3 months moving forward to incubation ? 

To be clear, this is not something against Harbor, but I see a potential "gray area" since it would be easier to go with sandbox and then jump into incubation, than do direct to incubation (which is harder).  
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