Why aren't you serious?
When my work starts getting inconsistent, I start getting all these noises about the fact that I am not serious about my work. Perceptions about my seriousness are generated from the consistency of my performance. If people say I am not serious, it means the consistency of my work is below their expectations. It is important to reduce these noises as they travel very fast and they reduce trust and dent your success.
If people think you are serious about what your are doing, they'll put their trust on you. In today's time this is an achievement. Success is correlated with the amount of people who trust you with your job.