#19: The Stairs Are There, You Just Can’t See Them
Stairs, by nature, can sometimes create an optical illusion that you’re stepping in place. It gets even worse when the stairs are covered in a patterned carpet that makes it impossible to see where one step ends and the next one begins.

provided by constative.com
Yes, it might be hard to tell at first glance, but this person isn’t just standing on a carpet. He’s standing on a carpeted staircase! We’d be extra careful when walking down these stairs, taking our time on each one. Hopefully, there’s a handrail for support that isn’t pictured.