An OTP falls into the "something you have" category[1] whereas passwords are in the "something you know" category. Things you have are generally less convenien

An OTP falls into the "something you have" category[1] whereas passwords are in the "something you know" category. Things you have are generally less convenient than things you know - which is why they're typically the 2nd factor, not the first factor. [1] I'm assuming you need something to tell you the OTP - that you haven't memorized them all.