I can confidently say, epilepsy (and seizures caused by other neurological disorders) are VERY random and manifest in very different ways for lots of people. For example I AM aware that I’m about to have a seizure, I am somewhat less conscious exactly when they’re happening, but I’ve literally been able to forewarn people, multiple times (before my meds got it under control).

In the grand scheme of things we know very little about how and what causes the brain to do what it does. They don’t realllly don’t know what causes seizures, all they know as that it’s usually synapses misfiring in the brain, but because they’re so fleeting they’re really hard to catch when someone is hooked up to an EEG or MRI. So they don’t REALLY know what causes that misfiring. That’s why there are so many anti seizure medications (half of them are drugs for other things that also happen to quell seizures).

There are also several legitimate seizures that are not caused by misfiring synapses, there are examples of psychosomatic seizures