One of the ways you immediately know when someone is junior is when they "follow the book". They talk like they're reading from a script. They greet you with unnecessary formalities and communicate with you like they "think they should". There is absolutely nothing wrong with this except that it doesn't feel genuine and tells the person on the other end of the conversation that you're kind of new at this.
On the flip side, I was told recently that a client thought I was "too casual". My immediate reaction was embarrassment and then feeling that I needed to explain myself. I kept my cool and agreed that it was kind of my custom to deal with clients like people and that because of my long term relationships that I could get too comfortable sometimes.
It got me to start thinking.... hrmmm...maybe I AM too casual? Maybe I've gotten cavalier with how I talk to my customers. After all, they are still "customers". They should be treated with respect (which I think I do). This goes for candidates as well. My "style" is to make the other party comfortable with me by letting them know I'm not reading form a script and am sincere about my interests.
Have you ever been accused of being too formal or casual?