Opinions vary but when discussing problems they fall into design and / or build issues. Things like inadequate GI or higher output power supplies / boards are design problems. Misaligned light tubes and adjustments being off are build errors. It seems that WOZ followers give a wider pass for issues on WOZ and are quick to retort with a Stern comment , pun intended.
Anything man made can break or fail but opinions and what they are based on is funny to read at times.