I would assume that although the RAID specification itself does not detail the implementation, the manufacturer of the card would like to write the RAID implementation just once and reuse that in all their product lines?
Hence, the RAIDn (for example RAID6) implementation of the manufacturer would be the same piece of code, regardless of their product.
In real life, this does not seem to be so, and far from different RAID product lines being cross compatible, I have seen issues where for the SAME product/SKU, the version X RAID card cannot be used to swap for a version Y RAID card
Do most manufacturers indeed have cross compatible RAID cards and I happened to choose one that does things uniquely?
Why is this so?