Beyond Loudness: Subtle Audio Compliance Issues Newbies Face?

Hey everyone, as a documentary editor still finding my footing, especially with final delivery specs like EBU R128, I'm constantly trying to improve my audio game. I recently cut a short piece, mostly shot on an FX3 with an MKH 416, and while I thought I had the loudness nailed, I still got a note back about some compliance issues I didn't quite anticipate. It wasn't just 'too loud' or 'too quiet,' it felt... deeper. For those of you who've been doing this for a while, what are some of the more nuanced, less obvious 'loudness and compliance' mistakes you've seen beginners make? Things that aren't just about hitting the exact LUFS target, but perhaps about true peaks, inter-sample peaks, or even dynamic range that causes rejections? What are the subtle pitfalls that really trip people up when submitting for broadcast or streaming platforms?