A mentor of mine once told me "If you put your suit jacket on the back of a chair and lean back on it, your suit jacket will look as if you put it on the back of a chair and leaned back on it".
I often walk into restaurants or office buildings and see men in collared shirts sitting with their jackets all squashed behind them on their chairs. I never really understood this.
It is not necessary to remove your jacket if you are sitting at a restaurant, or in an office setting. Usually, I leave mine on all day. A man almost always looks better with his jacket on, and if the fit is right, it shouldn't be uncomfortable. (Also, keep in mind that a well tailored jacket can easily hide a not-so-well-tailored shirt).
However, if you really feel the need to take it off, most places where de-jacketing is appropriate should have a coat rack, coat check, or some kind of closet. So no more walking around in squashed wrinkled jackets.
Thanks for reading.
Yours in style,