Isn't "before the device turns on" a perfect time to display a security warning?

If I receive a warning, I need to find out what it means.

If my primary device is the one displaying the warning, the only way I can find out what it means is to dismiss the warning and then 1) google it or 2) ask someone.

1) doesn't tend to happen outside of the tech bubble. 2) happens way way later, if it happens at all, as the odds of someone you can ask being around when it happens is slim. And more importantly, you need to make a phone call / check your email / do something with social media which is more important than the warning, as the warning can be dismissed and life can go on.

Odds are you forget about it entirely, and remember weeks later to ask a friend about somethingsomething boot warning insecure and then hand over your phone to them to have a look, at which point your friend loses their mind over what's happened, while the phone owner remains unconvinced it's really an issue since everything is still working correctly, and refuses to let their friend rebuild their phone for them as it'll take too long.

Source: happened to my friend's android phone. they still wont let me fix it.

And if they do see the warning? Where will they go to get more information? Will they use their computer? It’s becoming more common for people’s only “computer” being their mobile phone. What do they do when they do get the warning? Do they go to their local non existence “Android store”? Do they ask the clueless CSR from their carrier? Or do they just keep clicking continue like most people do on their computer?

How many people in other context like cars ignore warning lights?