It's not what you say, it's how you say it.
Continuing on the negativity theme, I am reminded of an interview I did when I was at Hewlett-Packard Company for a job which I was well qualified. I didn't get the job so when I followed up I was a bit surprised to hear the interviewer say "I detected some negativity." That's all it takes. I do appreciate her honesty. She detected what she perceived as negative and I was no longer a candidate for the job.
I have a lousy habit of saying things better left unsaid. We had a "Style Guide" at HP and it said to always assert things in a positive manner. It had tons of examples of how we speak naturally and often it is negative. We provide advice by saying "Don't, or You Shouldn't, etc., and the style guide made a point to put things in positive terms.
I grew up with parents who used sarcasm in their humor all the time. So most stories were riddled with negativity. I have found self-deprecation to be a useful humorous tool as well which is why I have way too many negative, bad habits.