Limited Goods Restocking

It's an artifact of the way limited trade goods work.

The limited trade goods only restock from 0:00 to 0:05 every 2 hours. They restock at the same time as the normal goods within this time frame.

If, for whatever reason, no restock occurs in that time frame, the limited goods will not restock.

That brings up a question, why wouldn't normal goods restock then? They're already full?

Normal goods restock at MOST every 5 minutes. For reasons I don't know, it takes between 5 and 6 minutes from one restock to the next.

So one possible way is for this restock to occur at just the wrong time. Anything else that causes the restock to be delayed could cause this as well (like a server malfunction).