Can you post a pic from further back to show more of the house. The spalshing is as good as anything I can guess

Bird landing pad ???

My guess is that they were installed below windows to direct rain so that the mulch below wouldn’t splash onto the brick. :p

My guess is that they were possibly used to support potted plants. The reason they are at an angle is probably because the supports for the shelves are flimsy and, when you add the weight of the pots, the shelf will move down to a near-horizontal position. I know that might sound weird, but I've never seen something like that in 45 years of home ownership and remodeling, and I can't imagine they serve any critical purpose. In addition, they're obviously something cobbled together by a home handyman, they're rather unattractive, and I'd remove them if it were my house.

I thought about party_music50's idea and agree that that is a possibility, too, but the way they are mounted means it's more likely to cause splashback against the window than serve a purpose of protecting the lower part of the house that is hidden behind that brick wall.

I don't know what was in the mind of the person who installed those, but it's definitely goofy. :-)

Kudzu, I considered that they might be platforms for window boxes but with that angle and the flimsy appearance of the hinges and materials, I decided probably not. OP said they aren’t on all windows, so first thing I’d do is look at the windows with them and determine what they have in common. If they’re all front windows, then probably plant platforms... if they’re all windows near brick walkways surrounded by mulch, then probably splash guards... etc.

ETA: they look more like an engineer’s creation than a handyman’s. Lol!

party_music50- I agree about having a better idea if we had a bigger picture. As an engineer myself, you’ve hurt my feelings, but as a handyman I would definitely have made something that didn’t look so gawdawful... ;-)

Lol! Sorry. I know a lot of engineers.... I am a software engineer... this looks to me like something an electrical engineer would do. Lol!

Here are some larger photos.

Has to be some sort of splash guard, as it is only thin gauge brake metal with galv. straps bent at an angle. Is there irrigation at all the windows that have this? I bet it was to keep the water from irrigation from spraying on or in the windows as the previous owner wanted his windows open.

Ironically, no. And there are other windows to have you regulation closer but do not have them.

Run the sprinklers and see what happens. Asking the sellers what the panels were for would take the fun out of guessing.