So there is this very special idea. And it is super important. And ever so critical. And you just need to make sure people get it. So you over-communicate. And you tell your staff/peers to over-communicate it, too. And you hit people on all channels: Email, Slack, meetings. You come at them from all sides. And you do this a lot. Just to make sure people get it.
Only they don't.
You merely numb people to what you have to say. Worse yet, they may start ignoring entire channels. I am sure you have seen this happen. Over-communication is the anthesis to effective communication.
Instead, have the critical ideas permeate everything you do. Re-enforce them on every turn. Use them to contextualize all the other stuff. Ask your staff/peers to internalize the important stuff and have it permeate their day-to-day operations, too.
Be consistent. But never noisy. That is how you turn over-communication into effective communication of the important.
It is ok to sound like a broken record. But make sure people pay attention to your song.