Ladders have their place, but walking under them is bad luck! The origin of this legend is, however, disputed. It could have its roots in Christian tradition, where walking into a triangle formed by a leaning ladder could be seen as breaking the Holy Trinity. Another possibility is that the shape resembles medieval gallows. A more practical concern is that maybe it's just not that safe to walk under an unattended ladder. The takeaway is: Put your ladder away when you’re done with it!