A client who comes to us for a software system and also needs a new website gets referred to our web brand — same team, same quality standard, no awkward handoff to a third party.
A developer ordering a custom workstation who also needs software built for their business can engage the software brand directly, knowing it's the same organisation with a shared understanding of their needs.
This is the practical advantage of an ecosystem over a single generalist brand — specialisation in positioning without fragmentation in delivery.