As someone who has been in hardware development for many years, EVERY bitcoin ASIC vendor has mainly had issues with the Board design, and Thermals/Mechanicals.

Once the chip design is done, its real easy to call the Chip FAB up and ask for chips...

HashFast - Original board VS Yoli 70% more performance with just a board change
KNC -  Ran out of VR modules because they bought an off the shelf part.  Then had Capacitors catch fire probably due to not spec for enough ripple current.
BFL-  Yea... Everything.  missed their power budget by 5x 
Cointerra-  Very complex board with heavy components on the backside.  cant be build fast.   Their issues are probably signal integrity and power related which explains the way less than 2Th.
Avalon-  Dont even want to talk about their problems.   Im still pissed.

ALL of these companies Im sure have trays of chips sitting on shelves doing nothing.     Their issues are that they cant build boards fast enough, or they dont know how to properly design a power regulator, or they cant cool the chip they designed.


-Smily