Started by https://github.com/strimzi/strimzi-kafka-operator/issues/3064

This feedback was received on the "Approving a rebalance proposal" procedure in the Cruise Control chapter of the Using AMQ Streams guide:

We've not explained the anatomy of an [optimization] proposal, so the reader is able to review it in any meaningful sense. Presumably by suggesting they "review" a proposal, there is the possibility that they might want to reject it (and generate another), but we need to explain why they might want to do that.

There are many possible reasons [why users might reject an optimization proposal]. The main ones might include a really huge amount of data moving or lots of InterBroker replica movements, but I think a true explanation would be quite in depth. It might be better to get the upstream Cruise Control community to improve their Wiki with this kind of information. I have a couple of WIP PR on the CC docs so I can add this discussion to them.

Improve the existing documentation by including discussion of why users might reject an optimization proposal. Where appropriate, link to the Cruise Control Wiki as the information there is developed.