Want to understand if there can be scenarios where a stake pool gets penalised even though it does not act maliciously. If this risk exists, what are the possible cases that can lead to penalties and is there an official documentation on it? For example: will there be penalties if the node goes offline?
Punishment is only indirect like Marek already wrote. Nevertheless, I would like to take the thought a little further: A node that, for example, is not online at the time it should be (to create the block in the slot) is "punished" by not getting a reward for the allocated block.
If this happens for a whole epoch (5 days), then of course the delegators will go to another pool because they are not satisfied with their rewards. (which will most likely threaten the existence of a pool).
However, there are no direct mechanisms in the protocol that deal with slashing (taking away stake from people).