Once upon a time, when people lived in little village and didn’t travel more than a few miles, there were people who could turn their hand to anything. They could shoe a horse, fix a leaky pipe and probably offer simple medical advice too. They were, in the truest sense, generalists.
The world has changed. Now the village is global. It’s easy to find people who specialise in exactly the skill we need. Generalists are no longer in demand, because given the choice, people prefer specialists.
Of course, the speaking profession is subject to the same trend. Clients want specialists, with in-depth knowledge of a topic or discipline. Knowing what you do is important, but so is knowing what you don’t do. As Mr Kenneth Rogers used to say “You got to know when to hold ’em, know when to fold ’em, Know when to walk away and know when to run.” Otherwise your speaking career is just a gamble.