My patio slider seems to be where the bird strikes occur, on the sliding part, since the rest is covered with shutters during the day. My windows don't stay clean, because i have a birdbath out in the yard & watching the birds, bunnies & other critters out there is "Kitty TV" to entertain my cat & she leaves nose prints on the inside.
Sometimes, the birds just knock themselves silly & once they get over the shock, they get up, shake their heads & fly off, but I've had quite a few that didn't survive & died while i watched them, hoping they'd get up, but didn't. I didn't want to rush out there & stress the poor things any more than they already were, by hovering over them or trying to scoop them up.
I had a strange one last fall (for me, anyway) when I heard a giant thud & knew something much larger than my usual doves & house finches & such had hit the patio slider & when I went to see what it was, I saw a large bird, which I think was a peregrine falcon, in a heap of feathers on my doormat. It sat there stunned for a few seconds & then, got up & flew off over the wall. It wasn't until I got to the patio door, that I saw a male Gambel's Quail off to the side on my patio, shuddering & breathing its last. When I picked it up, I noticed it had puncture marks on its chest, so I guess the falcon has already snagged it & then, flew into my patio door....kaboom. I chucked the dead quail over the wall, hoping the falcon would retrieve its dinner that it worked so hard for, but don't know if it did or not. If not, I'm sure something else got a free meal out of it, nothing ever goes to waste in the desert.