Originally Posted by XplusYplusZ

I think the problem is above the door line - possibly before it reaches your rain guards..
Where the roof metal meets the door, there's a gutter shaped seal on the tops of the doors (see picture below). I guess water is supposed to be caught by these gutters and runs off down under the vehicle via a pipe. But these gutters are not watertight. So water passes between the gutter and the roof metal and then pools on the inner door seal - which is not designed to handle pooling water. There's nowhere for it to go, so it pools and pools until you open the door, at which point it hydrates your seat. The only fix I can think of is to have a rubber seal attached to the roof line which forces water into the gutter and prevents water seeping inside the door frame.