Certainly a big issue is scale. For example if your company grows sufficiently large, there are people who do not know how at least one of your products works a

Certainly a big issue is scale. For example if your company grows sufficiently large, there are people who do not know how at least one of your products works at your company. You could fix this by partitioning who supports what, but even that won't work completely. Is your accountant going to do support for your enterprise or consumer products?