I asked this question on a SE site I'm not particularly familiar with, which got put on hold because part of the question asked for a product recommendation which is apparently off limits - fair enough, and silly me. No argument from me.
However, I got no notification - meaning here something in the 'inbox' or similar - it had been put on hold (I did get a notification for the one answer). Had I got a notification, I would simply have deleted the limb of the question (the recommendation) that was off-topic. It's a bit late now.
Related: Send authors an inbox message if their question gets closed - that is slightly different as it would be good to know as soon as your question gets put on hold, not only after (I'm told) 6 days when it is finally closed. Though I would clearly support getting notified when it is closed too.
Is there a reason questioners do not get alerted if their question gets put on hold? I'm asking this on meta.SE as I suspect this issue is pervasive to all sites.