I have three electrical panels in the house and with each one, one of the face screws is under the cover as seen in the picture. So it's clearly intentional. What's the purpose of it?
I can see that the screw was over the cover at one time by the marks in the paint. This leads me to wonder whether bulging the cover by keeping that screw behind may have let the latch operate easier.
That's pretty "screwy" looking, lol. Ok that's a bad joke... It appears to not be for a latch, but without inspecting it myself, who knows ? Looks more like a screw that was left in the panel frame prior to the cover needing to go back on...
Most latch acres I've seen are not near the outside edges of the panel cover, but much rather closer towards the opening of the panel cover.
These type of are made for more commercial / industrial type of applications, as the breakers are held in place by screws to their related buss.