I'm thinking of my breath. It stinks but I'm too lazy to brush it
Why don't you want to put in effort to brush your teeth?
It takes too much effort to properly brush
You should properly brush your teeth. This is so that you don't form a bad impression on other people if they smell your bad breath.
I'm sure nobody cares if I have bad breath. I don't want to go through the trouble and brush it.
Bad breath is not the only concern you should worry about. By not brushing your teeth you will end up with cavities, yellow teeth, and it could contribute to gingivitis.