Normal implies that no failure caused it to happen. Water entered through no fault of the rider or equipment.
It's normal for water to enter the wheel when riding in the rain.
That doesn't mean it's normal to leave the water in the wheel.
It's normal to get a flat tire when riding.
That doesn't mean it's normal to keep riding on the flat.
Hope that cleared things up
I actually thought we settled on the fact that water in the wheel is not normal at all, it's just "not unusual." Or common at best, depending on your experiences.