Why don't commercial passenger safety videos ever explain policy instead of merely dictating it? British Airways announced and published their new in-flight passenger safety video:


                
            

I'd like to draw your attention to two pieces of instruction given in the video, but also stated in every passenger safety video I've ever seen on every airline I've flown:


Never inflate the life-vest inside the aircraft.
Always put on your own air-supply mask before assisting others.


These instructions are always given in a dogmatic or dictatorial, way - the airlines expect passengers to comply with these instructions despite never giving any the reason for these policies - and I'm concerned certain passengers would disregard the instructions because they think they know better (and I included myself in that category until I found out why these policies exist).

I understand the reasons, respectively, are:


While being inflated makes it harder to move around the plane when your torso just doubled in volume - more crucially: if the plane does take-on water it means you'll be trapped inside the plane because you won't be able to submerge yourself to access an underwater door or exit.
Useful consciousness at altitude is measured in seconds, not minutes, and you will likely be unconscious and suffering hypoxia if you get distracted - it will take you a good 10-15 seconds to put your own mask on, let alone someone else's. It's entirely possible you'll die or suffer serious brain damage in your selfless attempt to assist your child.


Before I was aware of these facts I simply assumed the reasons were more mundane: inflating your life-jacket would simply make things slightly harder for yourself, and you should don your own mask first simply because it's easier - and I thought that inflating my own jacket inside the plane would actually save me time, and that I believed I was perfectly capable of assisting family members with their masks before my own if I held my breath. While laughable when informed, I genuinely believed these facts about myself until fairly recently. It would not surprise me if many passengers today feel the same way about themselves.

I understand the the real reasons for the policies make for grim reading and putting those kinds of visceral descriptions in the videos would spook passengers - but I assumed that because the videos never give any dire warnings, and are always said with a cheerful tone of voice, that the instructions weren't all that important, so it would somehow be tolerable if I did my own thing and disregarded the rules because I thought I was acting in my own best interest.

So why don't they at least add some transparency and explanation, for example they could say:


Never inflate your life-jacket inside the aircraft so you can fit through smaller openings and to avoid being trapped if the aircraft takes on water.
Always put on your own air-supply mask first before assisting others because seconds matter in low-oxygen situations.


While the sample explanations I gave don't go into too much detail, they still make it clear to passengers that the consequences of noncompliance are serious, if not fatal - and could still be read with a cheery tone of vocie :)

I compare this to the problem with "Danger: Confined Space" warning signs: the layperson thinks a confined space is dangerous because they might casually bang their head on a low ceiling - no thought is paid towards the common, very real risks and dangers of dangerous gasses pooling in a narrow shaft - yet it isn't too much trouble to add a short message to the sign saying "Because of trapped carbon-monoxide and other gasses", for example. It's odd because we already have other explanatory danger signs like "High voltage" (don't touch it without gloves), "Moving parts" (don't touch it, period) and "Falling objects" (so wear a hard-hat) - so why not airline safety instructions?
There is no time. You need to convey the information in as little time as possible or people (those few that watch at all) lose interest and start doing other things.
Reasoning tends to invite arguments, there's always someone who thinks he knows better. You don't want that.
Simplicity. Make things as easy to understand as possible using simple words. That way less intelligent people and people who have trouble with your language are more likely to understand what's expected of them.


There might be other reasons, but those are the ones that come to mind.