A few decades ago, marketing was not as broad as it is today. You had a handful of TV, radio and print outlets and a well produced commercial could run at prime time and would reach everyone. Now, there are niche and segment markets, making specialization essential.
In specializing, a business must be very clear on what it can easily deliver or risk the loss of credibility. This principle also applies in leadership. Your offering has to be precise and focused or folks may unfollow you.
You probably are not the best at everything, but what can you deliver effortlessly and consistently? In what ways can people count on you without fear? What aspects of life are you solid in? I see good leaders who look bad because they dabble into areas of weak delivery, make promises and constantly fail people while ignoring their place of strength.
I am a writer. I write every day. I have poured in the hours necessary to develop my gift and I can deliver effortlessly every time without fail. When it comes to writing, I am solid and have credibility.