From the article "Modes are not always bad. (1)Modes cause issues if they make computers behave in unexpected ways. However, if the modes themselves are obvious

From the article "Modes are not always bad. (1)Modes cause issues if they make computers behave in unexpected ways. However, if the modes themselves are obvious to the user, (2)if it is always clear how to exit the current mode, and (3)if the modes interfere with as few of the user’s actions as possible, these issues disappear." VI screws up in all of this (1) (2) and (3).