Aveline
How do flies and wasps get into the house but can't get out again? (Asking for two frazzled cats)
Perhaps because like birds they cannot actually see a pane of glass and therefore cannot work out which part of a window is actually open.
Having two exasperated cats myself, I just tell them flies are stupid and that if the cats sit still long enough the flies will come within reach to be caught. And that wasps and bees sting, so let me deal with them.
The cats watch in admiration when I trap bees or wasps by placing a glass over them against the window and sliding an old postcard over the top of the glass.