That is a pretty reasonable way of looking at it. One of the things that made NetApp interesting when I was there was ONTap, a completely custom OS with one memory space and no user mode. When you thought about it made sense, all you need for a NAS box is a really feature rich ethernet driver :-). Anyway, what it meant was that NetApp would uncover problems in CPUs and Chipsets that nobody in the "PC" world would ever see. Race conditions on the frontside bus, PCI express traffic that would freeze up the chipset etc. It was also true of drive firmware. Drives have all these commands which look good in the manual except no PC ever calls them in production. As a result they don't get a lot of testing. We discovered that 'write zeros' which was a command for zeroing out a disk, on some firmware revs was "write mostly zeros, except when you don't." Never good when you're trying to initialize RAID stripes. As a result there was always a "Netapp version" of the drive firmware which had been qualified but customers always believed it was just a way of preventing them from using commodity drives[1].

Any time you step off the beaten path and try to use a complex technology in an "unusual" way, you are blazing a trail which may not have been traveled before. Always good to be on the lookout for undocumented bugs.

[1] It did have that effect but it wasn't the motivation.