
"“Then six months later you need to buy some more, and that box isn’t available any more."
We once needed a more powerful desktop than the company's standard "Office" issue. Tesco had a suitable branded one going cheap - but the company insisted we buy a "business" model from the manufacturer at a significant mark-up. The brand and spec was the same - but the company reasoning was that the manufacturer guaranteed to supply specific "business" models for some extended time.
We bought two. Later on we decided to buy another one as a hardware spare - as our IT department were quoting lead times of several weeks for any repairs for a non-standard box. It then transpired that although the case and model didn't change - the manufacturer couldn't guarantee that the motherboard would be the same. As we needed interchangeable identical units this was a problem. Not long after it turned out that the particular "business" model would no longer be available anyway.
So we paid a premium for a non-existent guarantee of availability.