When you change the pen mode, it sticks to the change (as it should). But if you go back to see which one you have selected at the moment, it shows the default (regular pen thickness, black color), so users think they are stuck with a kind of pen or color they don't want anymore. You have to go change it on both pen style AND color in order to go back to normal or back to where you want.

It would be more straightforward if what you see is what you get. Please check on the attached video for a better explanation.