The problem with chat is the interruptive, thoughtless nature of it. In a large organization, you want durability that you won't get from chat.
Internal Q&A, forums, and email all work because you can have long-form conversations on them but an important consideration is discoverability. If a new user wants to find out why X is true for some service, they'd better be able to do that without interrupting someone else.
Internal Q&A, forums, and email all work because you can have long-form conversations on them but an important consideration is discoverability. If a new user wants to find out why X is true for some service, they'd better be able to do that without interrupting someone else.