Mystery of the incorrect password

Recently I reset the password of a site on an old laptop. The password was man@best. At a friend's place I tried logging on to the site with the password man@best. However the password wouldn't work. My gut feeling said that the password would work on the old laptop. However I could not exactly say why. Once I got back home, sure enough the password worked when entered through the old laptop. I then realized that the left shift key of the old laptop had ceased to function. I use my left thumb to press left shift key and index finger to press the @ key. However on the old laptop since the left shift key was not functional, the password was actually man2best. Pressing the left shift key had no effect and instead of typing @ it was typing the letter 2. Since the password field shows stars or dots, I couldn't tell. I was glad to uncover this mystery.