Why should we use effective illustrations?
Illustrations grow your imagination. When we use photography we limit the imagination of our users to what is presented before them. Illustrations give our users just the right amount of room for interpretation and help them imagine themselves in that situation.
What is user interface error?
Interface error is the state or condition when the app cannot do what the user wants. It usually happens in three typical cases: the app fails to do what's requested (literally, like there is no such technical possibility or function) the app cannot understand the input from the user (or the input is invalid)