Strong passwords are requirment for many applications, including your point-of-sale system. This is a good thing as it's important to restrict access to potentially senstive information.
But strong passwords can also be a bit of a pain. 12 characters in length and including numbers, symbols, lower case and uppercase. And typing all of that in with customers waiting to check out? Yeah, we don't think that's easy either.
The alternative to dealing with password hassle at the point-of-sale is biometric fingerprint readers. Instead of typing in a long complicated, difficult to remember password, employees type in a 2 digit code and then login using their fingerprint. It's crazy easy and more secure because it makes it impossible for employees to share passwords.
Almost every smart phone is equipped with a fingerprint sensor for easy device access these days. Why would your POS system be any different?