Hold it tight: A lesson from the Red Sea
This summer, during a liveaboard in the Red Sea, I witnessed a scene that every videographer fears, but which luckily had a happy ending.
Arsim, one of my dive buddies, performed the classic back roll from the zodiac. Everything was textbook, except that a moment after entering the water, his GoPro decided to continue the descent… all on its own!
Luckily for him, the guide had quick reflexes and grabbed it on the fly as it was sinking.
It ended well, actually very well.
The disturbing thing is that the camera was secured. It was attached to his BCD with a classic, top-brand coil lanyard. The problem? The plastic gave way. Probably stress accumulated over time, or perhaps a manufacturing defect, caused the attachment point to snap clean off.

This episode confirms my rule: never trust clips 100%.
Whenever I find myself in ‘critical’ situations (like entering the water) or when there is no seabed close beneath me, I always hold the GoPro firmly in my hand: the lanyard must be an extra security measure, not the only guarantee.
I check the clips visually and by touch several times, especially before entry, at the usual 5 meters during the group check, and before starting the ascent. Furthermore, I keep an eye on the attachments regularly throughout the dive, because in the past I have already found clips open or unhooked.
Trust is good, but holding it tight in your fist is definitely better.
In short: clip it on, but keep a tight grip.