Daily inspirational quotes have an effect on people in several ways, a number of of which, we aren't sensitive of. You can meet a person with a jacket with a "you can do it!" expression printed out on it and hey! It provides you with the motivation to try and do something which you have already been unlikely of conducting. On top of that, looking at a cup or even a plush toy with the the words, "someone likes you" forces you to understand your own importance as a person.