E/W are real abilities that can hit a human player who owns and operates a mouse and keyboard; Q is not. Generally if you get hit by nami q, you messed up. For example by not paying attention to an unwarded bush.

As the nami player you can try to look for times when people will walk into a Q, but I prefer to just think of it as a fake ability. Only if someone is already cced will it land, and your R is a cc but it's also pretty slow, although it's wide enough to R->Q someone close to you without a dash. It's a lot easier to follow a champ who lives solely to cc people like galio with bubble.